Falling down and in total disrepair, something that's dilapidated is going to need a lot of fixing up.

Sure, there might be crooked floorboards, mice scurrying underfoot, and pieces missing from the ceiling, but that dilapidated house does come with one perk: a cheaper price tag! Dilapidated is a word that implies deterioration, often because of neglect. So if you don’t take care of things, they can become dilapidated. That goes for houses, tree forts, relationships, health — you name it!

Definitions of dilapidated

adj in deplorable condition

bedraggled, broken-down, derelict, ramshackle, tatterdemalion, tumble-down
harmed or injured or spoiled