Quoting is unpaid work that has to be controlled. A survey, a drawing and an estimate can absorb half a day, so knowing how many quotes actually convert is what tells a one-person business which enquiries to decline.
The workshop and the van fight for the same week. Days spent fitting are days not making, and a schedule that ignores that produces a backlog in the workshop and a customer waiting at home.
Material prices do not hold. Timber and sheet goods move enough that a quote written in March and accepted in June can lose its margin, so quotes need a validity date and a materials figure that can be checked.
A deposit is not a courtesy. Timber cut for a specific alcove has no resale value, so money taken before the material is bought is what protects a small business from a cancellation it cannot absorb.