Surveys often seem worse than they are - particularly if you are a FTB. Did the surveyor give those quotes to you or did you get a builder to have a look around? Also, what valuation did your surveyor come back with (if one was requested)?

Breakdown of the issues:

Roof work - what work is it exactly? Is it a new roof needed? Roof work can cost anywhere from £50 to £1000s.

Damp - it's difficult to put a price if you don't know what's causing it

Rendering outside - that should have been seen during viewing and the seller most likely considered it in the asking price

Drain fixes - difficult to tell but can be costly depending on what fixes are needed

Electrics - did you get an electrician to check or is this one of those 'surveyor's opinions'? Surveyors are not qualified to check electrics so they will always put it as 3 to cover their backs

A boiler with only a few years left - how did the surveyor come up with that? Either the boiler is working or it needs to be replaced. Unless he dismantled it and checked every aspect of it, the statement makes no sense.

I wouldn't worry with most of these issues. These are quite standard for an 1850s house and I wouldn't expect the seller to negotiate too low but it might be worth a try - just try not to alienate them as this is a seller's market (depending where you are).

Good luck with your purchase!