Yes, but not recently.
Sold my Atari 2600 collection back in 1986 when I started to get into 8-bit computers and bought a C-64C. Then when I started to get into retro gaming in the mid 90's, I bought a 2600 and a whole bunch of games for dirt cheap.
Sold my Atari 1040ST set-up and collection (ya, not a console), in 1994. Missed all the great games I had and bought a 1040STE for dirt cheap in 1996 and now have a massive ST collection.
Sold my Saturn and Dreamcast collections in like 2002. Regretted it and missed all the great games I had and rebought those consoles a few years latter for dirt cheap. My Dreamcast collection kinda hurt, because I had a bunch of rare Dreamcast collectables from the time, like launch catalogs and magazines, a complete Official Dreamcast Magazine collection w/demo discs, a bunch of stuff bought directly from Sega, limited edition controllers, games, etc. Stuff that rarely shows up on ebay and unless you watch it like a hawk, you'll miss it.