I've never had anyone ask me that, though I'd probably give a random number if asked. That seems like a old fashioned tire-kicker's question, someone who's looking for "an angle" to chip away at the price. I don't expect to sell anything to those types, they annoy me enough that I won't usually bargain with them at all.

I occasionally get the silly "why are you selling it?" question. That also seems like a used car buying tactic, where the buyer is hoping an honest seller will disclose some non-obvious problem. I'm always tempted to reply "it's way too fast for me," but I typically answer that one honestly.