1. Which window style fits the opening?
Double-hung, casement, slider, awning and picture windows operate differently. The right choice depends on ventilation, cleaning access, furniture placement, exterior clearance and the look of the home. Do not assume the existing style is the only practical option.
2. Is this a replacement or new-construction installation?
A replacement window commonly fits within an existing frame. A new-construction or full-frame window may involve the surrounding trim, flashing, siding or wall opening. Ask what will remain, what will be removed and how the opening will be protected from water.
3. What glass package is being quoted?
Compare the complete glass package rather than focusing on one label. Ask whether the quote includes double- or triple-pane glass, Low-E coatings, gas fills, spacers and any tempered, obscure or laminated glass required for the location. The best choice depends on the opening and project goals.
4. Which options are included?
Interior and exterior colors, grids, screens, hardware, locks and specialty shapes can change availability, appearance and price. Confirm the exact selections before comparing two quotes. A lower total may simply include fewer options.
5. Who verifies the final measurements?
Homeowner measurements are useful for an initial estimate, but custom products should not be ordered until the openings and installation conditions are verified. Ask who is responsible for the final dimensions and what happens if an opening requires additional work.
6. What is included in installation?
Clarify removal of existing units, disposal, interior and exterior trim, insulation, sealants, flashing, cleanup and any finish work. Also ask how concealed damage or out-of-square openings are handled if discovered after removal.
7. What warranty applies?
Product, glass, hardware and labor coverage may be different. Ask for the current written warranty for the exact product and whether registration or other steps are required. Avoid relying on a verbal summary alone.
8. What is the expected ordering process?
Custom windows are manufactured to the selected sizes and options. Ask what information is needed, when selections become final, how changes are handled and what conditions could affect the anticipated schedule.
Compare the whole project
The most useful comparison is not simply the lowest price per window. Compare product configuration, installation scope, service, warranty information and the responsibility for verifying final dimensions. Clear details reduce surprises later.