I've mostly-bought, sight unseen ... basically negotiate the entire deal, make it clear that if my inspection & drive agree with the seller's description, I'll pay such and such a price -- and also that if anything is obviously not so, or if the seller tries a different price, I'll walk immediately.
I've done this often since '90 when I first did it, didn't want to drive 80mi just to haggle with a salesdroid and find out we weren't compatible.
Last time, we flew to Vancouver BC (from CA USA) and bought a car for tons less than local (and way fewer miles... er, km), even with import fees. Worked out great.
That works out better for both parties. I don't mind somebody asking if I'll take less once they have talked to me and decided they are interested; but when I get an email or text saying "what's the least you will take" or "$xxx, cash" without even asking anything about it I don't bother to reply.
When I sold my BH the guy called and asked enough so that I knew he was interested; so we agreed on a price if he came up and liked it.
Then he asked "will you take a check"... it was a Sunday and banks are closed. If he had waited until he got here I would have said no, but I agreed and had time to do a search and found that he was a straight shooter.