I think the limit here is 7 cars a year before you become a dealer? It may also be different if you can tie it to your business. Maybe that is outdated info.
Any running car in good shape down here is worth some money - a whole family could live in that car. About 3 years ago, I had to really search to find someone a creampuff '05 LeSabre with similar miles for less than $6K. Unfortunately, that car needed the gaskets and valve covers done as well as some other stuff. The single previous owner kept up on oil changes and other obvious maintenance, but never touched the coolant or brake fluid. It was a mess, but after putting a little time and money into it, it has been relatively troublefree for about 100K additional miles so far - aside from the window motors, an alternator, A/C leak, etc. All-in-all, I think the total outlay so far has been just over $8K, which is great considering it is driven every single day - a little over 30K miles a year.
What cracks me up is that I had an '89 Oldsmobile 98 Touring Sedan in the late 80's (well - in '89), the Buick drives exactly the same, but with some additional body roll. If feels the same, sounds the same, it doesn't look as good (I preferred the straight lines of the older models).