The 92-94 C2 5 spd Coupe Market hasn't cooled one bit. I've been following/trying to buy a nice condition, mostly original car for awhile and here's my breakdown.
Excellent condition cars - original, low miles, fully sorted - 60k below mileage or so = $75k plus plus - these are very rare (Holt Motorsport quality cars). Expect huge premiums for rare colors like Mint, Signal Green, Maritime Blue etc...
Good condition, no stories or rust, under 100k, maybe a rebuild, original paint etc... = $65k to $55k
Well sorted, clean modded cars can range from $50k upwards easily.
Couple good drivers pop up once in awhile. This supposedly has a pending in sale in less than 24 hours. Probably could of got mid $50s easily if marketed correctly.
https://lasvegas.craigslist.org/cto/6168272875.html
The 89-91 C2's and C4's on average can be bought for 10-20% less. If you are looking for an original, good, honest car it has been becoming harder and harder unless your budget is open. Way more demand than supply in the 964 coupe world.
I know Cabs and Targas go for less also but again the goods ones don't come cheap by any means.
The thing about the 964 Coupes is that they didn't produce allot of them compared to other 911 models and a huge percentage have been neglected and abused over the years (seems like the majority of the Porsche community crapped on them till 2014 or so). Look up Pelican and Rennlist member - Cobalt - posts. He's one of the most knowledgable posters when it comes to the 964.
Best of luck with your search.