1. Observe and protect
Record the symptoms, take safe steps to prevent things from getting worse, and pull together relevant history on the property.
2. Evaluate the house and site
The evaluation covers installation method, flashing, sill condition, frame material, and glass package -- weighed against Kentucky's cold, damp winters and long, humid summers, not just which brand gets picked.
3. Define a written scope
Nail down preparation, protection measures, materials, access, permits, testing, cleanup, finish restoration, exclusions, and change-order handling in writing.
4. Compare providers
Confirm each provider's credentials and weigh the reasoning and scope boundaries behind their numbers, not just the bottom line.
5. Inspect closeout
Wrap-up should confirm testing, cleanup, paperwork, warranty documentation, and any ongoing maintenance that's now the homeowner's job.