Get clean database, clean server files and clean client.
It's not complicated, paying to someone to do this for you will be a bad idea,
you have to learn from the setup process and to deal with it by yourself,
on the other hand get used to trust people as little as possible.
There are a lot of guides, threads, websites and also videos.
In my mind, the best way to learn how to do that is that site:

(I've learned from there).
Yes, you can control everything ( rates, drops, prices, everything.. ).
Good Luck