I bought a used 95 GMC 2500 conversion van 4 years ago, and it has worked out great as a tow vehicle. It had about 130k on it, and I did have some maintenance expenses - alternator, AC compressor, fuel pump, brakes, tie rods/ball joints. But at $4200, there was plenty of budget left for those items. It tows our 16' open trailer with car/tires/spares easily, and provides a better than tent sleeping space at the track. It also makes it easy to get the kids to the track, and carries lots of people when it needs to.

It is a great option for budget towing. I would recomend that you look at 250 or 2500 variants, and use air shocks (mine came with them).