Yeah, only ever sold 1 myself - a black Energon Unicron. I sold it because I was 'upgrading' to the 2010 Takara movie-accurate version. I couldn't justify having both (well, I could have to myself but not the wife).

Most of my purchases have been thoroughly thought-out therefore I can't foresee a situation whereby I would sell them en masse. Each one is a treasured piece.

When I pass them onto my children though, it will be a different story. If they ever suffer financial hardship, then I couldn't blame them if they had to sell off all or part of the collection. It will be theirs to do with as they please. Until then, I'll continue to enjoy it for the remainder of my life time.