Condition sets the hours, not the vehicle
Two identical cars can be a one-stage afternoon and a three-day rescue. Quoting before inspection is quoting blind.

Paint correction
Correction is the service most often sold on hope. The shops that do it profitably inspect first, document the condition, and quote a stage — not a result.

What the work actually involves
Two identical cars can be a one-stage afternoon and a three-day rescue. Quoting before inspection is quoting blind.
Clear coat is finite. What you are selling is a defined stage of improvement, and the customer needs to have agreed to that in writing.
The evidence of the work is the reason for the price, and it is also the reason for the next referral.
In ManePilot

Questions
Yes. A job can be created from an enquiry and priced once you have seen the paint, with the estimate sent for approval before work starts.
Each stage can be its own service with its own duration and price, including per vehicle type.
Related
Set up your services once, and the schedule, booking page and invoices all work from them.