I think prices are widely regional based on demand. In my neck of the woods, Fox bodies were either stashed away in the garage, or driven year round. The later is a killer because the salt has taken it's toll on the car by this point, and you'll find guys asking $3-4K for something with holes as big as my head in the strut towers, that have been beat on, badly modified, and have 8-9 owners by now. I looked at 1-2 of these cars as something to drive around and not car if it gets dinged up, and they were total POS cars with owners claiming "these cars are worth $4-5K all day long" Turned me off and I started looking at Sn95's which tend to be cheaper up here and still stock and 1-2 owner cars.
Clean, 1-2 owner garaged cars pop up for sale once in a while in the $10K range. No idea what they sell for, but browsing the local CL, there's maybe 2 of those...and one is asking $13K.
Then you go down south, and it seems they are still a dime a dozen. I see guys saying they pick up clean cars for $4K or so.
The SoCal market seems to be a huge one for Foxes, and demand pretty high out there. Another region where I see higher prices.