Doing business with someone who won't communicate with you before the sale, and who won't accept returns after the sale, sounds like a potential headache in the making. I'd steer clear.
And I say this as someone who typically has no particular objection to buying and selling via eBay.
Yeah, maybe you could still dispute things using eBay's guarantee, but come on.
I know that if I walked into a local store for a suit, and the salesperson refused to talk to me, and the sign on the wall stated that I can only examine the suit after I pay for it and it's delivered to me in a week or so, and no returns will be accepted if I'm not satisfied with the suit, there's no way I'd buy a suit from that store. Even if the prices were low.
But that's just me. Maybe you have more faith than I do that the universe will make everything come out right for you.