Match the equipment first
Get the complete model numbers, not just the brand or product tier. Ask for the proposed heating size, efficiency rating, heating stages, blower type, and controls. Confirm which accessories are included and which are optional. Manufacturer product pages can list several sizes and equipment-specific warranty conditions under one product name. Carrier 59TP6 product and warranty information.
A more expensive model is not automatically a better fit. Ask what each difference changes for the problem you want solved. If your concern is an uneven room, require a separate explanation of how the proposal addresses it.
Match the work around the furnace
Ask each quote to state removal and disposal, installation, venting changes, controls, required electrical or gas work, applicable permits and inspections, startup checks, and any home-related work excluded. Identify the responsible party and price for other-trade work. Do not let “complete installation” hide those boundaries.
A proper fit also needs a home-specific load calculation, which estimates the heating your house needs. ENERGY STAR's installation guidance calls for correct sizing and airflow, rather than assuming the existing size was correct. ENERGY STAR quality installation.
Compare the protection after installation
Separate equipment parts coverage from contractor labor coverage. Ask who registers the equipment, whether deadlines apply, what documentation you receive, and who handles a covered problem. Read the actual model's warranty, rather than treating a headline warranty length as complete coverage.
Keep financing, conditional incentives, and optional service plans separate from the base project. A smaller monthly payment does not establish a lower price. Compare the same payment basis and clearly named exclusions.
Use the difference to ask a better question
Send each provider a short request: “These are the models and included items I understand. What work in your proposal accounts for the difference, and what is excluded?” If one identifies necessary work that the other omitted, ask the other whether it is required and what adding it costs.
If the higher price rests only on a broad quality claim, request concrete details. If the lower price cannot explain sizing, startup checks, or responsibilities, resolve those gaps before choosing it.
The next step is a written comparison with the same equipment facts, project boundaries, warranty terms, and payment basis. Choose the proposal that makes the work and its fit clear at a price your household can accept.