I recently came across a dwelling with many dampness related issues, from multiple sources.
As a structure with multiple levels, leak points came from all over the building.
Rendered wall sheet cracking had allowed for wall moisture in all 3 floor levels to the extent that the removal of the external wall board sheeting was recommended to rectify this issue.
Cracked mortar to the tiled roof top area and failed sealant joints had allowed for moisture ingress to the ceiling area below. Rectification work would require the ceiling to be removed, as well as the tiling grout joints requiring removal and re grouting. The flooring on the third level had leaked and allowed moisture to soak into the flooring substrate and cause swelling and subsequent tile cracking. To rectify this area, the tiling would need to be removed and the flooring substrate replaced.
An out of view box gutter had blocked due to a curtain blowing into it and allowing the box guttering to overflow. The box gutter overflow however was positioned over the cracked wall sheeting. This allowed for leaking into the wall areas of the rooms below.
Moisture had leaked right down to the ground floor ceilings and floor areas.
Lack of painting maintenance had also allowed for the window trim timbers to have excessive wood rot, as the timbers were located on the second and third storey.
On this same house the tiled laundry floor area had excessive cracking with moisture visibly leaking out of the cracks.
My job as an inspector is not to judge the property and suggest if the client should or should not purchase it, but to advise on the faults.