I had 2 Suburban 4x4 with the 7.4L one (99) I bought with 220K and the other I bought (96) for with 130K. Both of them were under $3.5K but needed a few odds and ends. The higher mileage one had leaking power steering hoses which isn't that uncommon. There brake system uses the power steering pump to power the brakes instead of a vacuum assist diaphragm so you really want to watch the fluid level. The older one had rear ac problems because the lines that run under the chassis to the rear were leaking. That is an expensive job so don't let a seller just tell you that it needs some freon. Be watchful the 7.4L tends to have hot start issues because of the OEM injectors and/or fuel pressure regulator. 2 out of 3 of my 7.4L tow vehicles had it but I just dealt with it. The common mod is newer Bosch 3 or 4 hole injectors that are common ($200-$300) across many cars (incl Mustang 5.0L) that people install with new fp regulator. Do not buy overhauled or rebuilt OEM's because the flaw is in the design not being dirty or clogged. They drip fuel in the manifold after shutting down which causes the truck to be overly rich at startup requiring longer cranking times. They both towed my 8K trailer with no problem.
Don't neglect to look at Excursions V-10 their prices are dropping if you don't mind higher miles. Locally I see them 3K-5K with miles under 200K. I also had one of them with 90K miles with the 4.30 rear gear that I put a lot of trouble free miles towing across the county. Either platform I consider great but you will get better mileage out of the Excursion and it has more interior room I believe.
