Before hiring a generator installer, ask how the proposed system was sized, what it will actually power, what transfer and load-management equipment is included, how the fuel supply and generator location were evaluated, who will handle permits and inspections, and exactly what is included in the written price. You should also know who is doing the electrical and fuel work, what licenses and insurance apply, how warranty service works, and what happens during startup and handoff.
A useful installer conversation should make the design easier to understand, not harder. A contractor should be able to explain the assumptions behind the recommendation and put the important scope, equipment, responsibilities, and exclusions in writing. For a permanent standby generator, this page is a hiring checklist - not a substitute for a site-specific electrical or fuel-system design.
Generator installer questions at a glance
Use the same core questions with each company so you can compare proposals on more than the total price.
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How did you determine the generator size for my home?
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Which loads will the system back up, and which will it not back up?
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What transfer switch and load-management equipment are included?
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Does my existing electrical system need any additional work?
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Which fuel source are you designing around, and how will fuel capacity be verified?
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Why is this generator location appropriate for the exact model?
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What permits, inspections, utility coordination, or HOA approvals are part of the project?
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Who will perform the electrical work, fuel work, site work, and restoration?
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What licenses, insurance, and manufacturer credentials can I verify?
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What exact generator, transfer equipment, accessories, and controls are included in the quote?
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What is excluded from the price, and what could lead to a change order?
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What equipment warranty and workmanship warranty apply?
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How will the system be tested and handed over after installation?
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What maintenance is required, and who provides service after the installation?
Questions about sizing and what the generator will power
1. How did you determine the generator size for my home?
Ask the installer to explain the loads they used, which equipment has meaningful starting demand, what they assumed may run at the same time, and whether the proposed generator’s output changes with the selected fuel. A generator should be selected around the loads you want to support and the equipment’s real operating requirements, not from home square footage alone.
If you are still deciding what needs backup, review the sizing process in What Size Generator Do I Need for My House? before comparing quotes. A planning worksheet can help you organize loads, but the final design should come from the installer or qualified electrical professional who can verify the actual equipment and installation conditions.
2. Which loads will the system back up - and which will it not?
The words “whole-house generator” do not always mean every electrical load can run at the same time without limits. Ask whether the proposal is intended to support the full panel, selected circuits, or a whole-panel arrangement that relies on load management to temporarily shed lower-priority equipment.
Have the installer name the major loads included in the design, especially central air conditioning or heat pumps, electric heat, well pumps, sump pumps, water heaters, ranges, dryers, pool equipment, EV charging, and other large loads. If a load is excluded or controlled, ask how you will know that before an outage.
3. What transfer switch and load-management equipment are included?
A permanently connected standby generator is part of a larger backup-power system. Ask for the exact transfer equipment and any load-management devices in the proposal, what they control, and why that arrangement fits your backup goals.
Transfer equipment separates utility power from generator power and is a key part of preventing unsafe backfeeding. The installer should be able to explain the automatic transfer sequence at a homeowner level without expecting you to make wiring decisions yourself. See Generator Transfer Switches: A Homeowner’s Guide for the role of the transfer equipment.
4. Does my existing electrical system need additional work?
Ask what the installer observed at the service equipment and panel, whether there is adequate space and capacity for the proposed configuration, and whether the project includes any panel, service, disconnect, surge protection, subpanel, or load-management work.
A main-breaker rating by itself does not prove that an upgrade is or is not required. The answer can depend on the existing service configuration, connected loads, transfer equipment, available capacity, utility requirements, and local rules. If the proposal includes an upgrade, ask what specific condition makes it necessary. See Do You Need a Panel Upgrade for a Generator?.
Questions about fuel supply and generator placement
5. Which fuel source are you designing around, and how will the supply be verified?
Most residential standby generators use natural gas or propane. Ask which fuel the quoted output is based on, whether the existing fuel supply can support the generator along with other appliances, and who is responsible for verifying the meter, regulator, piping, or tank requirements for the exact model.
Do not treat an existing gas meter or propane tank as proof that the fuel system is adequate. Fuel pressure, capacity, pipe or tank configuration, other connected appliances, and local requirements can change the scope. The installer should identify who will perform and permit any fuel-system work. For a broader comparison, see Natural Gas vs. Propane Generator.
6. Why is this proposed generator location appropriate?
Ask the installer to explain the location using the exact generator model, its installation instructions, access for future service, exhaust direction, nearby doors, windows and air intakes, drainage or flood exposure, property constraints, noise considerations, and local requirements.
There is no single setback that should be copied from a generic article and applied to every standby generator. Placement depends on the equipment listing and installation manual plus the requirements adopted where you live. If the property has tight side yards, flood concerns, easements, HOA restrictions, or nearby mechanical equipment, those issues should be resolved before the final site is accepted. See Where Can a Whole-House Generator Be Installed?.
Questions about the installer, permits, and project scope
7. What licenses and insurance can I verify?
Ask which company and licensed trade professional will be responsible for the electrical work and, when fuel work is needed, who is qualified to perform that work in your jurisdiction. Licensing structures vary by state and locality, so verify the license with the appropriate state or local authority rather than relying only on a logo, badge, or marketing claim.
Also ask for proof of current insurance and whether subcontractors are covered appropriately for their work. The Federal Trade Commission recommends checking contractor licensing with state or county government and asking for proof of insurance before hiring a home-improvement contractor.
8. Are you authorized or certified for the generator brand?
Manufacturer authorization is different from a government-issued trade license. A dealer or installer may have brand-specific training, access to warranty service, startup tools, or service programs, but those benefits and requirements vary by manufacturer.
If the installer emphasizes a certification level, ask what it means for your project and verify it through the manufacturer. Also confirm whether the brand requires authorized installation, registration, startup, or service for any part of the warranty. Do not assume one manufacturer’s dealer rules apply to another brand.
9. Who will perform each part of the job?
A standby-generator project can involve electrical work, fuel work, equipment delivery, a pad or mounting system, trenching, permits, inspection coordination, utility interaction, landscaping or hardscape restoration, and final startup. One company may handle everything, or several trades may be involved.
Ask for the responsible party for each major scope item and whether any work is subcontracted. If a problem appears later at the boundary between the electrical and fuel work, you should know who owns the callback.
10. What permits and inspections are required, and who handles them?
Permit and inspection requirements vary by jurisdiction, equipment, fuel type, and project scope. Ask the installer which approvals they expect, which company will obtain them, who schedules inspections, and how you will know the permits are closed.
If utility coordination or an HOA approval is needed, ask who is responsible and whether that work is included in the schedule and price. The installer should be able to distinguish a known local requirement from an assumption that still needs confirmation.
11. What exactly is included in the written quote?
The quote should identify the generator model, transfer equipment, major accessories and controls, installation labor, site or pad work, electrical work, fuel work, trenching if needed, permits, startup, taxes or fees when applicable, and restoration responsibilities. Ask for the meaningful exclusions, not just the included items.
If two quotes differ substantially, compare scope before comparing price. One proposal may include fuel-system work, load management, permits, restoration, or service that another quote leaves outside the base price. The Whole-House Generator Cost guide can help you organize those cost drivers.
12. What could change the price after I sign?
Ask the installer to name the conditions that could trigger a change order. Common planning variables can include an inadequate fuel supply, unexpected trenching or access conditions, electrical changes discovered during evaluation, a required location change, added load-management equipment, or local requirements that were not known when the estimate was prepared.
You do not need a promise that nothing will change. You need a clear process for how scope changes are documented, priced, and approved before extra work is performed.
Questions about the contract, startup, warranty, and long-term service
13. What warranty applies to the equipment and to the installation work?
Separate the manufacturer’s equipment warranty from any workmanship warranty offered by the installer. Ask what is covered, what is excluded, who files a warranty claim, whether travel or diagnostic labor can be charged, and whether registration or maintenance records affect coverage.
Get the applicable warranty documents for the exact equipment rather than relying on a verbal summary. If the installer sells an extended warranty or service agreement, ask what it adds beyond the standard manufacturer coverage.
14. How will the system be tested and handed over?
Ask what the installer will verify before the project is considered complete. A professional handoff should include system startup and functional testing of the generator and transfer equipment, required inspections, confirmation of the configured loads or load-management behavior, and homeowner documentation for normal operation and service.
You should receive the model and serial information, applicable manuals, warranty and registration information, permit or inspection records available to the homeowner, and contact information for service. The installer can demonstrate normal owner-facing controls and explain what should be left to a technician. See Whole-House Generator Installation: What to Expect.
15. What maintenance will the generator need, and who will provide service?
Maintenance intervals and procedures depend on the exact generator model, operating hours, environment, and manufacturer instructions. Ask what routine service the model requires, what the homeowner is expected to monitor, what requires a technician, and whether the installing company provides scheduled maintenance and warranty service.
Also ask how service requests are handled after installation, especially if the company is a sales organization that uses a different contractor for maintenance.
Generator installer red flags worth a follow-up
A single issue does not automatically prove an installer is unqualified, but these are reasons to slow down and get a clearer answer before signing:
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The generator size is justified only by home square footage, with no discussion of the loads you want to support.
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The proposal does not identify the exact generator and transfer equipment or explain what will and will not operate during an outage.
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The company gives a universal placement rule without checking the exact model, the property, and local requirements.
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No one clearly owns the electrical scope, fuel scope, permits, inspections, or final startup.
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The contractor will not provide license or insurance information that you can verify.
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Important exclusions are left verbal, or the price is presented without a written scope.
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You are pressured to sign immediately, pay the full amount up front, or accept financing you have not had time to compare.
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Warranty and service responsibility becomes unclear once you ask what happens after installation.
The Federal Trade Commission recommends getting multiple estimates, reviewing written contracts carefully, verifying contractor licensing and insurance, and not automatically choosing the lowest bid. For generator work, compare the system design and scope line by line before comparing the final number.
How to compare two generator installation quotes
Normalize the proposals before deciding which is less expensive. Put the following items side by side and mark anything that is missing or described differently:
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Generator manufacturer, model, fuel configuration, and rated output used for the proposal.
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Backup objective: whole-panel, selected circuits, or load-managed whole-home coverage.
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Transfer switch and load-management equipment.
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Electrical upgrades or enabling work.
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Fuel-system work and which trade is responsible.
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Generator location, pad or mounting work, trenching, and restoration.
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Permits, inspections, utility or HOA coordination.
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Startup, testing, owner handoff, remote monitoring setup if included, and documentation.
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Equipment warranty, workmanship warranty, maintenance plan, and service contact.
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Total price, payment schedule, exclusions, allowances, and change-order process.
A good next step before you sign
Use this checklist with more than one installer and ask each company to put the proposed equipment, backed-up loads, major installation scope, permit responsibility, warranty terms, exclusions, and price in writing. Then compare the proposals against the same backup goal.
If you are still deciding what type of system you need, start with Whole-House Generators: A Homeowner’s Guide. If you already know you want a standby system, review Who Installs Whole-House Generators?, the generator sizing guide, and the installation process before your final quote comparison.
Related guides
Sources
Source access date: September 24, 2026.
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Federal Trade Commission (FTC), Consumer Advice - How To Avoid a Home Improvement Scam (opens in a new tab). July 2022; accessed September 24, 2026.
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Electrical Safety Foundation International (ESFI) - Generator Safety (opens in a new tab). Publication date not stated on page; accessed September 24, 2026.
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Generac Power Systems - Your Guide to Home Standby Generator Ownership (Home Standby Buyers Guide) (opens in a new tab). 2024 version; accessed September 24, 2026.
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Cummins Inc. - How to buy your home generator online (opens in a new tab). Undated webpage; accessed September 24, 2026.
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Rehlko / KOHLER Home Energy - Buy Your Kohler Generator Online or In-Store - Get a Kohler Certified Installation (opens in a new tab). Undated webpage; accessed September 24, 2026.