The obvious answer to the problem is DON'T SELL BIKES.
Just buy 'em.
Sometimes they get broke and thrown away,
or worn down to leaky nubs, and rolled into the back shed.
Could keep tuned, clean, and running.
But never sold.
I sold a bike once...
I just wish I could afford a bat cave to keep multiple bikes in...that would be niiice. Apartments + the nomadic urge to spontaneously pick up and change zip codes don't mix with owning multiple bikes. If I could, I'd keep the frankenmonster 900 for life, add a Streetfighter 848 this spring, an old Gixxer for the track, a dual sport of some kind, plus have 2 additional builds going on at once at all times....