The challenge is how to cover my costs on the extremely small job that doesn't have a troubleshoot/diagnostic. Whether you have a small service charge or do free estimates, the job is starting out as a loss.
My challenge is recovering that loss on the small jobs. I've calculated the average time to answer the phone, drive to the job, meet the client, spend time checking their project, pricing their project, presenting the price, invoice, collection, setup, cleanup, trip back, and data entry at 1.5 hours.
So, the challenge is setting the price for a 1/4 or 1/2 hour job that I have 2 hours in.