Please feel free to let me know why it would be wrong for me to do that, as I'm not trying to be unethical.
Also: corrected the dodgy formatting!
suppose you reverse-engineer the app and the old programmer finds out. he says "hey, that's my work, you are not allowed to do that" and sues you. if he's as vindictive and unproductive as you claim, that seems a likely outcome.
what you're talking about is throwing good money and effort after bad. you're digging yourself into a deep, dark hole. you and the programmer could be taking revenge shots at each other for years.
starting over puts you at zero, which is way better than sinking deeper and deeper into negative numbers.
okay, first, you can't use html in an hn post for formatting. you should go back and add two-return-key paragraph breaks, so your post will be readable.
I had the exact same thing happen to me the other day when trying to submit a poll, it popped up <p> tags all over the place, so I'm sure it's not the guys fault.I had to go back and edit the thread to make it readable after someone pointed it out to me.
by the way, by putting a couple of blank spaces at the beginning of the quote, your comment is causing the page width to get stretched out.
second, getting someone to "reverse engineer" an existing app is a very bad idea. you're already in a bad situation, that would make it even worse.
assuming you find someone to do this, they are going to be morally questionable. i, for one, would never agree to do such a thing, not for any price.
if you're not happy with the work you're getting, you should have said so a long time ago. if the terms you've negotiated so far allow you to do so, i'd offer him some smaller amount for the source code and call it a day. if he says no, hire another coder to start again from scratch.
2500 bucks is not very much money to lose. i just lost six months of my time working on a startup that didn't pan out, for which i received a grand total of 1500 bucks. given how much i was making at my last full-time job, that's an opportunity cost to me of about 50 grand. but i'm sure as hell not going to make things worse by mucking around in the situation any longer. i took my lumps and i'm moving on.