I've been an Airhead owner (79 RS) for three months. After wrenching for the first two, I finally put 109 miles on her in three days. And with winter on my heels I'll be getting it ready for storage in December. So with very little experience, being a total novice I'm not qualified to make any accurate evaluations about vintage, collectibility, or rarity. Would someone please explain why this eBay sale fetched so much dinero?