I used to sew for people, not a tailor really but I have made several wardrobes for people. Of course they paid me for the services. I enjoyed it most of the time. It was great to make something someone wanted. like a black velvet suit, or square dance dress, and see the joy on their faces when it was done. It paid for my sewing machine, and extra play money.
I did get taken advantage of by my inlaws though. I swear that every single time they visited I had to hem at least two pair of pants for my father in law. He appreciated it so it was not too bad. But My MIL used to ask me if I could "run this up" on my machine all the time. I always thought it was funny that she thought it was so easy.
The worst favor I ever had to do was when my inlaws came to visit and they both had red jackets that they had started putting campground patches on. MIL had started hand sewing on some and they looked awful. I told her sure, it didn't look like to many, no prob. Well, then she came in with a huge zip lock bag full of more patches, two of each. S I spent two or three days working on getting those patches on. I am a bit of a perfectionist so it took a long time. Plus there was enough to go down each front and down the arms. We saved the back for more patches. The actual sewing part was not fun, but they were both so grateful and loved my work so it was worth it.