I would do the very opposite of what L Gebhard says - offer him less. In fact offer him $350 and let him talk you up to $500. If you're in the right place at the right time (which it sounds like you are) and if the seller has no interest in trying his hand at ebay than it is most certainly a buyer's market. In fact, the seller is very lucky he found you because the scrap yard wouldn't give him more than $25 for this setup.
Good luck. Assuming you do get it, you will need to get it home and use it. Scroll down this page to 138 manual and brochure. http://www.durst-pro-usa.com/resources.php. It shows you how to take it apart into I think it is five pieces so it will fit in a car. I brought two from Detroit to Cleveland in an SUV. These will also teach you how to use it. There is lots of other good stuff on that link.
If you ever go up to 8x10 take a look at the mislabeled 108 (should be 138S) Durst in my gallery. 12x12 Cold light Aristo head with modifications done by Michael Mutmansky.
The 138 comes apart easily. All you need is a large phillips head screwdriver to remove the condenser head. All the collar locks along the column are tightened and loosened by hand. Once apart you'll have no problem fitting it into a compact car.
It is a good thing that this enlarger has a set of condensers and some spare bulbs. You cannot get a more even lightsource for b/w than a durst condenser head.
As I recall, if you separate the column into two sections you need a big #4 phillips. Be careful of the
heavy spring which counterbalances the head. These enlargers have all kinds of fine-tuning options,
and a lot of them were made, so if you need parts you can often cannibalize another "as is" one.
That's what I did, and ended up with two fully refurbished one in excellent working order (one with
a colorhead and the other modified for 8X10 film with a cold light). Finding extra negative carriers in
good condition affordably can take a bit of patience, but I picked up a mint one a few months ago
for about thirty bucks - in the good ole days they cost $1200 (for a spare carrier alone)! These vintage Durst enlargers are simply the best! You never get machining like that nowadays.
As said I have four.. with all kinds of extras.. Got it for free (!!) So Stephanie, IF you find you need some extras PM me.. I'll proberly be able to help you out. For a "price" you can't refuse.. ;-)
I think all I'm going to come away needing is an 80mm lens for medium format. It's a really complete kit. Husband is on board with the idea.
Right now the plan is this: if I can't come up with the money for the big one by the end of November, I'm going to buy the Omega smaller format one off of him and use that until I can. It would at least give me the ability to do contact prints without relying on a bare bulb. Then, as soon as I get the money, I call him back and we arrange pick-up of the other one.
This guy sounds kind of cool. He shoots 4x5 and scans. He also used to shoot plates, so I kind of want to see those when I go. Basically, I'm excited to meet this guy, enlarger or no.