Quoted from Frax:

Isn't it going to have to be moved anyways? Unless you're depending on someone else to move the machine around you other valuable games without damaging them, or it's a total hassle to keep it in the garage until it sells....just get it moved, IMO.

Quoted from egyptrus:

I've actually had the problem you're thinking you might have. I had a new to the hobby person commmit to buing a six million dollar man that I had for sale (not through ebay though so it wasn't a contractual committment). He had seen enough pictures and was coming with the intent to buy that game. I had moved it so it was closest to the door of my gameroom and away from my other games.
He walked in, took about a six second look (one for each million, I presume) at the game and said "that won't do, I don't like it". Mind you, he never turned the game on or played it, just declared it unworthy from looking at it. I asked him if he expected the game to be different than what he had seen in the pictures. He didn't reply.
He then started walking around my gameroom and stopped in front of Fish Tales. He got all excited about how colorful the game was (clearly he was basing his decision on looks at this point) and asked if he could buy that one. I told him that not only was it not for sale but it was in a different price category than the six million dollar man game.
Long story short is that I ended up selling him the Fish Tales because he agreed to pay the outrageous price I shot him when he said "give me a number".
So, it can happen but I wouldn't move the game until he gets there. If he suddenly seems interested in the other games, that's fine, but he's contractually committed to buying the game he bought on ebay so I wouldn't worry about it. Who knows, he may offer to buy one of your other games, if you're so inclined to sell one.
Dave