Ask for a written estimate after diagnosis. A low service-call charge is not the same as a low complete repair cost.
Check the line items
- Diagnostic or service-call fee, and whether it is credited.
- Parts, labor, taxes and any second-visit charge.
- What happens if the proposed repair does not solve the problem.
- Written warranty terms for parts and labor.
- Whether additional work requires your approval.
Compare replacement fairly
Include delivery, installation, removal, required accessories and any changes needed for the replacement to fit. Use actual written prices in the worksheet. Do not use a universal percentage rule as a substitute for diagnosis or safety advice.