what you expect and what you get are sadly often two different things.
Choose to do business with people who treat you the way you would treat them and don't be afraid to walk away if things start going the other direction.
if you have questions i would make sure they are asked and answered prior to payment, or you many not get them. I bought birds from people when i was starting out, and did not know what questions to ask before purchase, i have gone back after purchase with questions i really wanted answered ( ie origins of the brids i bought) and they would not tell me.
so if they wont answer your questions prior to purchase, that would be a deal breaker for me.