Crikey. I never fail to be surprised at the lack of maintenance some houses have had. For so many people, it's out of sight, out of mind, until the roof starts leaking or whatever.
Do you still want to buy the house with all the work? If so, you need to let the vendor know you're considering dropping the rice for remedial works and want to pop round with a few trades and price it up. Then if they agree:
A general builder can give a quote for these:
brickwork on one wall dubious - needs repointing or what? Builder can price it
all chimneys mortar to be replaced and capped (have shrubs growing in them which won't help the damp!) - builder/ roofer
tiles loose and broken on roof - have to say this wouldn't worry me in itself, I would chalk it up to general maintenance of a roof and would budget for it regardless of survey
no soakaway - and no rainwater drains either? I've seen a few 70s houses in my neck of the woods where they just discharge to the ground. One of these houses also had a great big crack next to the drain, between a newer extension and the original building. Pointed it out to the vendor and she had no idea the rainwater was supposed to go somewhere (other than causing subsidence to her new extension)
Again, builder can have a quick look, but maybe you'll also have a drainage co out anyway to look at...
cess pit has roots in it (original and old)
damp walls in 2 rooms - what sort of damp? inappropriate plaster? DPC breached? You can usually get a damp/timber company to do a damp survey for free that will give you the likely cost of repair. Chances are your EA will know one as this comes up all the time. They can probably go get the keys and pop round and write you a report without you being there
electrics need checking and possibly replacing - all surveys say this. What do you think? How old is it? Have you seen the fuse box? Old or new style? An electrician might have a look for free and give you a quote but this one wouldn't faze me really.
If you're paying close to asking price, they'd be silly not to agree for a reduction of a few grand to get these things done as they'll come up in any survey. Then again, you can't really underestimate how unreasonable some vendors are, especially older people who've lived in a house for umpteen years, done no maintenance but have $$ signs in their eyes after the EA promises them top dollar... Families and people who have a genuine reason to move are generally more agreeable.