Undamaged, the bike is worth around $2,000, so, assuming it's otherwise in good shape, the price is fair. Looks like maybe $500 worth of damage if you source the tail off eBay, and not counting the fairing. If you're handy enough to fix the fairing and repaint it yourself, or if you don't care what it looks like, or if you''ll strip it and go naked, why not? The ad does say OBO, so, make a lowball offer and see what happens.