Oh interesting idea for a thread...we're renting so I can go mad on this as it isn't mine to sell 
Damp throughout ground floor, lots of spces between skirting and walls, etc etc and there is mould.
Cellar extremely damp
Much of wiring should be renewed
Only about 1 of the 7 windows opens, (this is just the ground floor) most have broken sash cord and are painted up
Rain coming in through roof
tiles and finials liberally falling down
guttering all full of plants and leaking fulsomely
gawd KNOWS how old the boilers in the top two flats are (ours we got replaced a few years ago, existing one was about mid eighties)
Basically it is a money pit and I'm kind of glad we don't own it as I'd want to knock it down and start again...