Negative arch!!!

[Joopin]

I'm currently looking at a 91 xj (in earlier post "found a cherokee"). My dad and I went to see it agian with the guy who is selling it. He said he used it for doing "estimates" for his buisness but he just got a chevy blazer recently.
He said that it used to sway back and forth uncontrollably when going 60 mph +. He said that someone fixed it for him so I looked and the front sway bars were new. When I was underneath the jeep I noticed that the rear leaf springs were drooping over the axle really bad. It wasn't even flat, it was in a negative arch. I pointed this out to my dad and he thinks that it must have been beat on by some of the guys workers. I don't know what to think about it. I have heard of this happening but never seen it. Is this normal for a 91?
Otherwise it seems like a good deal. The Kelly blue book value is $2910 and he is asking $1650 but wont go lower than $1500. Also my dad doesn't like the fact that he cant test drive it since it's not insured or registered.

[MudderChuck]

If you spent thirty seconds looking at the obvious stuff to check under a Jeep. You could burn two hours really fast. Without a test drive, I wouldn´t even consider it.
I usually figure how much in parts, I´m gonna have to stick in it and then figure what my time is worth. Double the parts cost, is a good estimate of what it will require, figure from there.
The last XJ I bought, I was looking almost six months, got antsy and bought one, I probably should have passed on it(guy liked to fix it himself and wasn´t very good at it).
Things to keep in mind, at about 60,000 or so, there is a large service reguired on the XJ. At a hundred thousand, the drivetrain is fairly worn (depending on oil changes). 130,000 or so usually requires a second starter and or alternator. Probably a variety of bearings and seals to change.

[Bounty__Hunter]

That spring sag can be normal for that old of a Jeep. Look very closely at each leaf spring, along the edges, and look for a broken leaf. If none, you're okay. Abuse will generally break a leaf.

An add-a-leaf or 2 new spring packs will fix you right up.

[Joopin]

Well since my dad was the one buying it, he passed on it. He was thinking along the same lines as Mudder Chuck. He didn't want to buy anything he couldn't test drive. He's gonna wait for the next deal... I was lookiing a whole year before I found my jeep, so I guess it will be worth it. Thanks for the info.

[Bounty__Hunter]

If the current owner is saying you can't test drive it for those reasons, sounds like they may be hiding something. I'd find somewhere to drive it.