Go to his house, in person, and check it out. Don't bring any more cash then you are willing to shell out. If everything looks good, offer him $100. Make sure to mention that you can't use the fittings, etc.
It's an a$$hole move, but people are much more likely to compromise on their price when you are there with cash in hand. Most of the time, they just want to get rid of it and make a few bucks. He will probably counter with $150, so offer $140.
It takes a bit of courage, but I used to work in sales.
If the fridge sucks, resell it for $75 or something.
I have done this on Craigslist many times. People tend to want to sell a bunch of items for X amount of money. Act interested, show up in person and lowball the hell out of them. Chances are you can get a 30% discount, then resell the items you don't need, individually, and you can pocket the stuff you wanted for next to nothing in the longrun.