After spending over one year working on a social network project for me using WordPress and BuddyPress, my programmer has disappeared, even though he got paid every single week, for the whole period. Yes, he's not dead as I used an email tracker to confirm and see he opens my emails, but he doesn't respond. It seems he got another job. I wonder why he just couldn't say so. And I even paid him an advance salary for work he hasn't done.

The problem is that I never asked for full documentation for most of the functions he coded in. And there were MANY functions for this 1+ year period, and some of them have bugs that he still didn't fix. Now it seems all confusing.

What's the first thing I should do now? How do I proceed?

I guess the first thing to do will be to get another programmer, but I want to start on the right foot by having all the current code documented so that any programmer can work on all the functions without issues.

Is that the first thing I should do? If yes, how do I go about it?

What's the standard type of documentation required for something like this? Can I get a programmer that will just do the documentation for all the codes and fix the bugs or is documentation not really important?

Also, do you think getting another "individual" programmer is better or get a company that has programmers working for them, so that if the programmer assigned to my project disappears, another can replace him, without my involvement? I feel this is the approach I should have taken in the beginning.