To end up with a complete collection like this one meant the individual had to seek out a lot of rare items, and pay the premiums for them. Obviously, too much money was spent to get to this point. IMHO, he'll never see it again, unless he is extremely lucky.
I have room full of systems and games, but all were acquired at closeout, garage sale and thrift store prices (next to nothing), except for those which were remnants from my youth. Purely sentimental and research value. It'll take a millennium for an Atari 2600 Pac-Man cartridge to become valuable, and my progeny will have ebay'ed it all for peanuts long before then.
Yeah, poor investment.