RE: be carefull you read the small print! The mid survey on my first place found a missing lintel above the front bay window. The double glazing was holding up the front of the house. I would never have picked that up and it could have been disasterous, as it was the owners paid to have it sorted.
Chef, damp proofin etcare wots known as jobs for the boys I have a friend in the trade ..... just phack em orf
RE: be carefull you read the small print! Mmm, spot on. Waste of money going for the top one. Every wall (especially in a old house) will give a damp reading at this time of the year. A slate can be re-fixed for £50 or do it yourself. As for timber treatment, it all depends on what they are saying is wrong with it. If you're happy with it all, don't drop ya money. Or, like you said, just knock £500 off as a goodwill gesture. Because they'll not get the work done anyway. And the tile will probably be claimed off their insurance as 'Storm' damage.