People who paid $30,000 a few years ago for nice restorations were comfortable that their investment would rise. Right now, if sold, they'd go at a loss. Never consider a classic car as a profit center. You can consider it as an investment, however, and you can insure it against loss unlike stocks.
Plain Jane 350 2bbl, nice or not, don't demand a lot simply because they aren't highly collectible as they are, and are no more or less valuable than a 6 cyl or non matching 400 car.
Vikki 1969 Goldenrod Yellow / black 400 convertible numbers matching