The range is useless if the sentence is missing
Wellholt publishes a low, a typical, and a high for a named job. A water heater of a named size and fuel, in the same closet. A furnace on the ducts that are already there. A roof with one layer removed. An attic of blown cellulose toward a stated R-value. If the quote does not say which of those jobs it is, you cannot put it next to the table. You can only wonder. Wondering is how a fair price and a padded one look the same.
Write the scope in their words, then in yours
Take the quote and underline the machine, the size, and what is not included. Then open the matching calculator and read the sentence under the typical column. If both sentences describe the same work, the number can be compared. If theirs adds a re-pipe, a liner, a second layer of shingles, or a panel, stop using the typical column. Those additions are allowed to cost more than the high number. The page says so. A contractor who lists them is not automatically expensive. A contractor who hides them inside “standard replacement” is the one the high column was built to catch.
Labor is not a personality
A city with labor at 1.30 times a national crew will sit higher than a city at 0.90 for the same sentence. That is hours and permitting, not a better furnace. Materials barely move. If you are comparing a quote in Boston with a memory of a price in Houston, you are comparing crews, not brands. The city page prints the labor factor for that reason. Use it before you decide the local price is an insult.
The yearly bill is not a discount
A heat pump that costs more to install is not “really” the furnace price minus a savings someone estimated. The bill calculator is a separate page, with degree days and an electric rate written down. Gas uses the price you type in the bar. It starts at $1.50 a therm only because a local gas tariff is not in the data. If a quote folds a rebate and a yearly savings into the install price, ask for the three numbers apart: the machine, the rebate, the assumed bill. You can check the bill. You cannot check a blended slogan.
One screenshot, one job
Do not send someone the whole city table and ask if it is fair. Send the row that matches the sentence. A roof and a bedroom of paint do not explain each other. The review date is on the city page. After that date, treat the row as old and say so, instead of defending a number the site has already stopped standing behind.