What to look for in a written quote
Check the scope, supplied parts, exclusions and the arrangements if the findings change.
Two quotes with the same total can cover different jobs. Read the description before comparing the numbers.
Parts and labor
The quote should identify the equipment or fitting supplied, the installation work and disposal. If you are supplying a fixture, make sure that is stated. A product warranty and an installation warranty cover different things.
Exclusions
Access through a wall, tile repair, electrical changes and permits may be separate items. Ask about anything the job appears to need that is absent from the document.
Changes
A repair may reveal a second fault. Agree on how the technician will explain the options and obtain your approval. Keep the accepted scope and any changes with the final invoice.