beat-up 
adjective informal
Worn out by overuse; in a state of disrepair.He started by getting into his beat-up old car and driving around the city going through people's garbage looking for things he could fix up and sell....
- Although we're rattling our way along Dumbarton Road in nothing but a beat-up Ford Fiesta it really feels like we're out here cruising on the edge of the world.
- There's a half-facetious saying there: whoever is driving the most beat-up car has right-of-way.