85 CRX HF 259,000 mile
 

Not mine but really clean CRX HF on eBay. Lots of miles but body looks clean
https://cgi.ebay.com/ebaymotors/Honda-CRX-CRX-HF-1985-Honda-CRX-HF-

those engines are not reliable

Looks like a nice clean HF indeed. @BIBI: why would the older HF engine not be reliable?

I've found mine to be extremely reliable, and in reading about them on forums dedicated to that body style people tend to remove perfectly good engines simply for more power, or try to kill them by not changing oil so they have an excuse to get a bigger engine.

It was ironic, with 259k miles on it, its without a doubt reliable.

Mine went 340,000+ miles before I swapped it to a VX (also for mileage). It is a wonderful little car. I just prefer FI and 93 hp from the VX (also, the VX is truly less problematical, over-all); however, were mine in this great condition I would probably have driven it longer as an HF. I have too many cars, or I'd definitely get this one.

At what price is this a good buy, and when would it start being overpriced?

That is the nice thing about Ebay, the market decides how much something is worth, I got my crx hf on Ebay a few years back for $700, and still have it, although I think I'm going to sell it to my brother who commutes 60 miles each way to work.
So figuring that the car dies of natural causes with good matenence, it should last another 100,000 to 200,000 miles or more, if the body is good almost anything else on it can be replaced, so it's really up to you as to how much you would pay for a car that's alot of fun to drive, in good shape and gets 50+mpg.