For those that use square footage for pricing do you use what the customer tells you or do you go on a site like Zillow to get the square footage
Square footage has nothing to do with windows or amounts and styles for bidding
Would highly recommend a system based on window count and style.
Responsibid has the option to use square footage or per pain or window count. They have a very complex system in the backend for square foot bidding. But it is very wise to always have in writing that the bid is subject to on site evaluation.