That's getting to the "monster" stage, in my opinion. :-) I think the plants get to about five or so feet tall--and your plant's probably going to reach that stage way before mine does thanks to the sauna that you reside in.
I think the seller is also being a little too ambitious--but then again, if the thing sells, then who am I to argue with her salesmanship? I've never seen a vanda priced like this. Usually it's the Cattleya walkerianas that are frequently listed for outlandish sums (although I did see yesterday that there's a bulbophyllum something or other listed for, like, $1700).