I just picked up a Neo-Geo Arcade Machine with 6 or 7 MVS carts and 1 JAMMA PCB (The Main Event). Got it all delivered to my shop for an even $450, but I tipped the driver $50 for being so careful with all of it and delivering in a timely fashion. My boss then bought me a 151 Multigame MVS Cart from Hong Kong, so now I have 7 MVS carts (3 or 4 with boxes and mini marquees) taking up space in my closet. Only minor complaints: My cab has woodgrain side panels, no original Neo-Geo side art, no light up credit display on the control panel, no headphone/memory card ports...but again that's no big deal to me anyway. Screen is in GREAT shape, and sounds amazing. Very very happy with it.
My brother bought a G.I. Joe Arcade and paid to have it shipped to his friends house (he was in the army and money was burning a hole in his pocket), and he ended up dropping $2,000 total including shipping. I love G.I. Joe and all, but that's FAAAAAR too much to pay in my opinon.
I also have a cocktail game called "Space Fever", made by Nintendo...was manufactured around 1979, pre-dated Space Invaders I believe, could be wrong. Picked it up for $100 with extra side panels and an extra monitor.