We started doing the repairs to our home because (1) its one hell of a lot cheaper, (2) we got tired of paying a lot of money to have things done and they were not done right. It's nearly impossible to find a good contractor around here; most of them are total idiots. And it's also the satisfaction thing.
I've had "professionals" come in, look at a problem, say it's fixed and charge me $100. Two months later, the problem is back. I had the plumber twice and my so called contractor brother in law look at the drain line on the kitchen sink because it was leaking. We played this game for about a year, it always started leaking again. Plumber says for $400 we will tear everything out and put all new in; that's fix it. Not on my budget, thank you.
I fixed it myself in a morning and cost was about $40. in supplies. The problem was that these idiots were not using the correct schedule of PVC pipe and putting it in unsupported. There is a dishwasher attached to that line. I got the correct schedule, new compression fittings, pipe strapping and put it all back together.
Funny, it hasn't leaked since. The dishwasher's hot water would warp the wrong schedule PVC pipe over time, the compression fitting wouldn't seal any more and the joint would start leaking. That's been a good 12+ years ago. The only repair we've done to that line was a new P trap last year.