Thanks for all the advice. I met with the seller this morning to look at the machines.
We was a very nice guy and I enjoyed speaking with him. He was gracious enough to show me his private collection of 135 machines. It was very impressive. http://www.pinball4all.com/collectionH.php
The machines were like the_pin_family said they were, a very good shop job. PF's were in excellent condition with very little wear. What he basically did was strip the machines and do a very good cleaning. Nothing was really replaced which was surprising. One of the ramps on ES has a crack, and he said you can buy a protector for that (Cliffy). I was thinking why didn't you replace the ramp or install the protector. I just can't understand why he would have stripped the machine and taken everything apart but not replace what was cracked and broken. That makes no sense to me. If you are spending the time to take everything apart, spend a few bucks and replace the parts that need replacing. If asked him about clear coating the PF. He said "That changes the game. The ball slides around instead of rolling" Looking at the PF's they were in very good shape, so that was not really an issue.
One thing that did rub me the wrong was that he said "I told a another guy he can have the Earthshaker for $3,000 unless I got a better offer. If you want it for $3500 it's yours" As a salesman I would never say anything like that to a potential customer.
He also had a Bad Cats for sale. Never seen or played one of those before. It was a fun machine but he wanted $3800 for that also. He had a Dirty Harry machine that he said he was waiting for Clint Eastwood to die and the value to go up before he was selling it.
All things considered, it was worth the 20 min. drive.