Hm, I got an offer for a spanish car a while ago, was a scam.
I don't want to say moketillos offer could be illegit, but nobody with his head in the right place should buy anything for close to 10000 bucks if he can't be sure to get it, especially if he uses a irreversible transaction like BTC.
And a car? How do you know it's in good shape (technically speaking) without looking at it?
But, well, if you wanted to take holidays in Spain anyway, than why not?
Just make sure to include the Bitcoin payment (including a fresh target address) in the contract.
That way, neither the buyer nor the seller can argue there was no transaction.