Don't send a mechanic quote until you know the profit
A lot of mobile mechanic jobs get priced as a round number. $120 for a battery. $350 for brakes. Then the job runs long, parts cost more, and the good week was actually break-even.
Before you send the quote, write down four things:
Labor hours and your real hourly rate, not the rate you wish you earned
Parts you will actually use on that job
Travel, call-out, and equipment time
The margin you need to stay in business
If the price does not cover that, do not send it. Raise the price or cut the scope.
That is the habit the Mechanic edition is built around: quote the job, cost the job, see the profit, then send.