Legal Question in Business Law in California

Re: contractor did bad work should he be paid

You left out one of the most important factors - is the contractor licensed?

Unlicensed contractors have almost zero legal rights, but on the other hand often have no ability to pay a judgment if sued in small claims or anywhere for that matter.

Licensed contractors generally have bonds and real assets to back up their liability for bad jobs, but they can also file mechanic's liens.

In order for LawGuru attorneys to give you a more useful answer, I suggest you re-submit your question and specify whether the guy has a license or not. Meanwhile I lean toward advising you not to pay.