In message , Another Dave
writes
1928 2-storey detached house. Top storey rendered and somebody put
cavity insulation in 10 years ago ( I've owned it for four years).

Rising damp at the rear and both ends of the upper story have got
penetrating damp - I think. Rather than get estimates from people with
vested interests, would I be better off paying a surveyor to tell me
definitively what's wrong and, if so, how much would he cost?

Get the professionals in to quote for work required and price, then DIY

obvious

--
geoff