I wouldn't say that the paint quality is an unknown. The seller clearly states "the paint is not good. It was painted Cobalt Candy Blue by the previous owner and did a poor job. It will need some minor bodywork and a repaint". As already stated, a (quality) paint job is going to be expensive, in part because the engine bay has to be painted as well as door jams, etc.Unknown paint quality, it was carb swapped, interior trim is hanging, no fender liner, no wiper... just a lot of HELL NO from me.
Paul hasn't mentioned what the asking price is, but if it's at the top end of what is expected for a '92 Notch then it very well might not be worth investing a lot of money in to bring it back. JMO. And the mileage definitely needs investigation once you pull a Carfax report. 58K seems pretty low for a Mustang that's been converted to carb and completely (economy) repainted. To paint the engine bay, the motor had to have been pulled, which again raises the question if the car was wrecked and re-built on a low budget.