Ok let me spell it out. We don't know if it's a few hundred dollars and it doesn't matter. We don't know why he was in prison, but if he got 12 years, it won't be drunk driving. If someone did sth before they're more likely to do it again. You got your work done, and didn't pay up. The guy can use a bit of cash to get back on their feet. Basically, there is no serious argument why you wouldn't pay the dude apart from you being a massive cunt, both morally and just general self preservation.

Honestly, I'd probably pay them what I owe plus interest - I can sleep well and the dude is going to be happy.