I gave away my NES to a friend after it had sat idle for a year or so in the late 80s. I'd love to have my original console and games now, so that'd be #1 even though none of it was rare or valuable. Also, we kept the games in the boxes until the boxes were falling apart and got thrown out, so I'd tell me to just put the boxes away somewhere. Of course, then that storage box probably would have gotten chucked at some point.

Starting collecting sooner since I only started 6 or so years ago comes to mind also, but realistically I wouldn't have taken that advice anyway since I had other stuff going on.