Look for musty smells, peeling paint, mould, damp patches, staining, crumbling plaster and signs of recent repainting that could conceal a problem. Structural warning signs can include large or stepped cracks, sloping floors, sticking doors or windows, bulging walls and roof movement. These clues do not prove a serious defect, but they merit further investigation before you commit to buying. Arrange an independent pre-purchase survey and ask a suitably qualified building or structural professional to assess any concerns; check current guidance with Citizens Information or a relevant professional.