If it doesn't start with a jump, I'd offer $100. Could have low compression or a burned exhaust valve with that kind of mileage. A compression test wouldn't be a bad idea.
Check all around the front control arm mounts
very carefully. I've seen them rot out in 3 different places. Most common are the "loops" that the front bushing bracket bolts to. But I have one that is rotten and flexing well above that area and another that rotted around the rear bushings. A front wheel pushed back towards the rear of the car is a very bad sign. Badly or unevenly worn front tires is a bad sign too. And so is pulling one way when accelerating and the other way while braking is bad too. Run away if it does that!
Is it worth $500? Not to me. But I got a '94 Metro that spent its life in Florida for $150.
And a lot of free ones that died from rust issues.