Questions covered in this guide
Compare the work behind the price
Enter the total from each written proposal, then separate any confirmed charges outside that total. Taxes and permit fees belong in the extra-cost field only if the proposal excludes them. A blank extra-cost field means the charges have not been confirmed; it does not mean all extra work is free.
Treat missing scope as an open question
Mark each scope item as confirmed, excluded or not sure. The tool lists discrepancies and generates questions for each contractor. An included item is not a judgment about workmanship or completeness. Ask for the exact models, measurements, installation method and warranty documents that make the proposals comparable.
Understand the calculation
Each known total is the quoted price plus the confirmed additional charges you enter, rounded to cents. The displayed difference is the absolute difference between those totals. No national price multiplier, local adjustment, financing charge or assumed price for unknown work is added. The tool never ranks contractors or recommends the lowest bidder.
Compare a written payment schedule
Optionally enter the monthly payment, the number of those payments, charges outside them and any additional final payment. Count each charge once: an ordinary last installment belongs in the payment count, not again in the additional-final-payment field. All fields must be confirmed before a schedule total appears. The gap against the cash project total can include financing charges, fees or different pricing; it is not an APR or interest calculation. The model assumes fixed payments and does not evaluate variable rates, deferred interest, future late charges or contractor quality.
Compare the details of your project
For roofing, apply the same possible decking-sheet quantity to each written allowance. Confirm equivalent sheet specifications and use the contractor’s actual included quantity and extra-sheet price. This is a scenario, not a prediction of hidden damage. For windows, compare opening counts and whether the existing frames stay or are replaced. A per-opening average cannot establish the same products or work. Unknown terms remain questions to resolve.
Sources and supported claims
ENERGY STAR advises comparing written, itemized estimates, including project cost, equipment details and warranty information, rather than choosing on price alone.
Source ↗ · national · Checked 2026-10-12
Andersen distinguishes insert replacement within a sound existing frame from full-frame work; matching installation scope is necessary when comparing window proposals.
Source ↗ · national · Checked 2026-10-12