I would pick a location close to you- look up the ART reports on the CDC website and you can see success rates. The study is only done every couple of years- but it is a good way to compare. There are also varied prices. I suggest you interview a couple and see what suits you and that you feel comfortable with the RE.
SSBD to you!
No honey, I have no experience with donor agencies.
Good luck and SSBD to you!
Melanie