You'll be better off finding a good breeder that will provide a quality animal and after sale support. As you mentioned the imported baby Biaks are usually aggressive (at least at the start) and will most likely have a variety of internal parasites. That "cheap" animal may not be such a deal in the long run. As for handling most GTP's can be handled but it will take time. Follow the link to an article that I wrote for Reptiles Magazine several years ago. It will give you some pointers.

Rico Walder
Signal Herpetoculture

Why Be Bitten article