Clayton, if he seems sketchy (he may well not be), if your gut is telling you to walk away, if his customer service isn't what you expect it to be....and this is only in the purchasing phase....then trust yourself. It may take you awhile to find the right snake from the right person but it's never time wasted in my mind.
Like Jon said, ask specific questions and expect clear, concise answers. Be a smart, informed buyer. It won't quarantee you'll never be ripped off but it lessens the odds somewhat.
Also we have an Inquiries section here at BPNet. You can post inquiries about breeders, etc. there to get the opinions of members that have had dealings with that person.