Used van advice please

[glatt]

I think my wife and I may have come to the conclusion that we want to buy a used mini-van. We've been kicking the idea around for a few years and are more serious than ever before. We have two kids. What do we buy?

It's an unusual situation for me, because we don't NEED a mini-van. We have been making do with our Geo Prizm. But there are times that we could use one. Relatives visit, we go on road trips, etc. I'm cheap. Mini-vans use a lot more gas than our Prizm. And they cost an arm and a leg when you buy them new.

When we were researching renting a minivan to drive up to Maine this summer, we found most were going to cost almost $1000 for the two weeks. I don't feel like throwing $1000 away on a rental. That's when I thought that buying a cheap used minivan might be the ticket.

I think we would only drive about 2K miles a year in a minivan if we got one. It would sit in our driveway for a month or so at a time, and then be driven across town when guests are here or will be taken on the highway for a few hours. Every year or two we will take a mutiple day road trip with it.

I guess my question is if you can let a car sit for a month at a time in between drives without it dying on you? If I buy a van with say 120K miles on it, can I expect it to last another 20K miles when it is being driven once a month? Where can I find a nice resource that will tell me about how to buy a used vehicle, and ranks used minivans? I've never bought a used car before, and don't know how to go about doing it. I've seen a wide range of prices in the paper for various models with various miles on them. Is a Toyota with 120K really worth the $4k price when you can get a Chrysler with 120K for half that?

Basically I'm looking for something that's cheap, big (7 passenger), and won't strand my family on a higway somewhere. Any ideas?

Thanks in advance.