Here are some problems you might expect to find when renovating.
Above is the house before renovation. Much of the damage was concealed.
rotted bathroom floor.
pipes through carrying beam, really bad
wires stripped, and sheet rocked over.
new foundation, bathroom floor
notched floor joists
cut floor joists, no support.
2nd floor addition needed attention
crumbling foundation, rotted sill. The downspouts did this
2nd floor bath
subfloor and framing needed to be replaced. This was an old staircase to the basement.