Parts are cheap, I listen to music or a podcast, I do all the “PITA” repairs (replacing wheel bearings, ball joints, tie rods, full brake service) that are really just labor in terms of professional repair cost, perform additional rust prevention, and for sale it goes when I feel a new grandma or grandpa would never give a hesitation to load it up with all their grandkids. They also see a very thorough interior cleaning, and a full exterior detail (including paint correction when required).
It has bought every very nice tool I could ever want, most are 20-30 hours of labor including acquisition, and I’m at the point where I have repeat customers (the put a 2nd alongside the first) and have direct referrals. Now the profit mostly goes towards putting a 2nd interesting car in the garage, and some towards moving up the ladder to try to earn more per vehicle.
Selling cars isn’t bad when you don’t have employees to pay, and it lets you sell really high quality stuff. I keep thinking of how much I couldn’t justify doing, and how much my product standards would suffer if I had to pay help.