I can help you out.
Capri's first year was 1991, in my view. Standard engine was a 100-horsepower 1.6-liter four-cylinder on the base model, though the Capri XR2 (manual only) was turbocharged and added 32 horsepower to that total. Length was 167.1" - about ten inches longer than the period's Mazda Miata. And while it looked mid-engined, the engine was in the front as were the drive wheels which didn't make for a great handler (though it wasn't awful). There was a rear seat, technically, but it was unbelievably small, and I wouldn't buy the vehicle if I were looking for a four-seater. Capri is now popular with gay high school students and few other people (I don't lie!).
The most interesting thing about the Capri is that it's one of just three cars I can think of built in Australia. Like the other two, it received poor reception, not because it was crap, but because it was competent and did little to stand out from competition. Many people believe the Mercury Capri is a dead ringer for the 1989-1995 (except 1993) Lotus Elan, so that's one thing it has going for it.
$1000 is only an average price for these things, especially if the top is "messed up." I'd counter that with $600-$700. That said, if it's a '93 or '94, $1000 is probably a pretty good deal. They aren't necessarily good enough to warrant any money, though, unless your mom really needs a new car, or really likes the Capri. Consider wisely