[78F350]

Prices are way up on all used cars right now, but $4-5K sounds pretty optimistic. I have not seen non-running cars go up in price nearly as much as general used cars. In 'showroom condition', $5k with a blown engine would probably be a hard sell for a '99. (1999 Boxsters are my favorite model year)

"...everything is pretty good condition wise" Can mean very different things to different people.
A blown motor from overheating can mean a lot of things too. It may be scrap or it may be fairly easy to repair. I'd bet on scrap if I was a buyer.

Generally I have seen 'rollers' sell for $2500 - $3500. If I buy one I'm looking at the parts value as my top dollar. I have bought a couple under $2000 that were in 'pretty good condition', but those deals don't show up often and don't last long when they do. The $1,200 car that STL bought is an outlier and not good as a data point. If it is common where he's at, I'll head there with my trailer ASAP.

Thoughts on price: New high-end tires, perfect paint, and a refreshed suspension should add a lot of value to a Boxster. A good used 2.5L engine can now cost about $3,000. DIY installation can add a few hundred in misc parts. A good paint job can cost significantly more. A nice set of Michelins installed is over $1,000. Updating a suspension that is over 20 years old can also run into thousands. Having a dealership do maintenance such as a coolant tank or water pump can easily run over $1,000. Fixing a car with cracked leather seats, windows not working properly, and a bad top can cost more than a replacement engine.