1. Observe and protect
Log the symptoms, take safe steps to stop further damage, and gather whatever history on the house is relevant.
2. Evaluate the house and site
This step weighs installation method, flashing, sill condition, frame material, glazing, and trim just as heavily as the window product itself.
3. Define a written scope
Document preparation, protection, materials, access, permits, testing, cleanup, finish restoration, exclusions, and change-order rules before work starts.
4. Compare providers
Check credentials and compare how each provider arrived at their number and where their scope stops, not just the final figure.
5. Inspect closeout
At closeout, confirm testing, cleanup, documentation, warranty terms, and what maintenance is now on you going forward.