Well, let's see.
First of all, the machine on the end (the orange DK Jr. cabinet) *IS* a MAME machine.
I bought two of those machines (Shinobi and Bucky O'Hare) for $100 each at an auction last year. Two weeks ago, I picked up the Heavy Barrel cabinet for $200. Last weekend at Super Auctions in Dallas, I picked up Road Riot 4WD ($175), Aero Fighters ($175), and Neo Geo - Double Dragon ($200). I also have Metal Slug and Puzzle Bobble for the Neo Geo.
If you are looking for games between about 1984 and 1994 then I would expect to pay between $100-$500 for games. "Classics" (Ms. Pac-Man and Galaga in particular) go for anywhere from $500-$1000, depending on condition. Newer games are insanely expensive (just saw a Harley Davidson game go for $3000).
Yeah, my kid's gonna be spoiled as shit. You can't see the Air Hockey table or Slot Machine from that shot. All that stuff is in my backyard in a 14x35 building with A/C and everything. Cool place to hang out when the guys are over (there's also a fridge, microwave, and poker table out there as well, along with my Atari 2600's, SNES, N64, PSX, and Genesis (the PS2 and Dreamcast stayed in the house)).
Flack