A useful comparison goes beyond the total price. Confirm the exact window series, style, glass package, color, grids, screens, installation method, trim work, disposal, permit responsibility, payment schedule, and both product and workmanship warranty terms. Ask each company to identify allowances and exclusions in writing.
Get the details in writing
A trustworthy proposal should identify the exact product and installation scope. If a term is important to your decision, ask that it be included in the agreement rather than relying on a verbal statement.