It might have been empty for years, originally in OK condition, but invaded by hordes of partying teenagers or tramps or something [hoping here that the story isn't that sad...]
I agree that people don't look past the superficial. We bought our house ludicrously cheap (well, actually ludicrously expensive, but cheap for SW London) - I mean at least £100k less than the market rate for similar sized houses - becaue it was scruffy and painted orange and crimson throughout. And dirty: occupied by divorcing couple, angry teenagers, many many cats and multiple smokers. But it was sound, and transformed by a lick of paint.