That Detomaso is overpriced, that's why it has been on the market for a very long time and hasn't sold.
About 2 years ago a Detomaso was sold, ready to rally with low stage miles, $6.5K worth of new Proflex in it and a heap of other good bits for $5K.
Before looking at buying any used race or rally car, homework needs to be done otherwise you could end up buying someone else's very expensive problems. This podcast covers buying used rally cars:
Buying a Rally Car - free MP3 Podcast