Actually, with a complete mame rom+chd set, if you cull out just the games that are non-working for that particular version you can save yourself a significant amount of space. Programs like clrmamepro, MCM, and ROMlister are your friends, especially if you're dealing with limited space.
Take the .145 complete set for example.
If you were crazy, you could use ROMlister to cut away all:
clones
non-playable
rhythm games (even when they're "playable" they're not exactly optimal)
fruit machines
pinmame
mahjong
quiz
and mature titles
You'd end up with ~20-25 gigs of game data. About 9 gigs in roms, and about 13 in chds (if you really cherry pick the chds.) You could even go back and put back any unique clones (like X-Men 6-player version, etc.) and you wouldn't effect those numbers much.
Console sets are even smaller when pared down a bit. Why, you might be able to fit Mame, NES, SNES, Genesis, and TG-16
functionally complete sets on a 32gb MicroSD card...
if you were crazy.

(I'm in the process of planning/building a system where the only moving parts are the controls.)
The lion's share of MAME's hard drive real estate are chds. Most of those chds are attached to non-playables, or rhythm games. A little picking and choosing there can go a long, LONG way.
Bump up a touch, to a 256gb SSD (~$200) and I'd guess you could do all of it in this way. Snaps, vids, your OS, the whole kaboodle, with plenty of room for add-ons later.