Sometimes i'm thinking about selling but then i realize it's not worth it most of the time. The money i'll get from most of my stuff is so little that i rather keep said stuff instead. I did sell a few things because they offered me enough money that i couldn't refuse (such as a rare Mega Drive pack) but other than that i see no reason to sell an item for a couple of euros or something.
Even if i decide to sell my whole collection, it will probably take months to do it without completely killing it and the total amount of money will probably be something that i can make in half that time anyway. It just isn't worth the trouble.
As for space, my collection isn't that big. I have plenty of consoles but only a few games for each. And i only have 3 or 4 of them connected, all the others i can emulate fine so i keep them in a special cabinet for display purposes only. All their cables, gamepads, etc, are stored separately in small boxes in the storage. I like my cabinet and it has room for a couple of more consoles (i'd like a Neo-Geo AES).
Other than that, i don't care that much, i don't actively collect stuff, most of the things i have are either stuff from my childhood that survived, stuff that i got for free from people who wanted to get rid of old junk, or stuff that i found in recycle bins of just very cheap to pass.
I do hoard a lot of digital stuff though...
Talk of Retroarch meeting the needs isn't quite correct, over the weekend gone I tried emulating Gamecube games via Dolphin and RetroArch on the Series X and had mixed results at best, couldn't get rid of the side borders, no matter what I changed, and F-Zero GX and Wave Race 2001 either won't work, or the in game-screen gets "jumpy" just doesn't stay stable....yet Mario Kart DD and Mario Tennis don't have that problem (aside from the side borders), thats why I am considering getting a Wii for the first time, because you won't have to mess around with any RetroArch to get the cube games to play, and you can re-visit the greatness of F-Zero GX with ease..
Dolphin isn't very goon in RetroArch. However, the standalone is MUCH better, though you can only use it on a PC.