We have got penetrating damp coming through the walls so I am going to give the outside a good coat of waterproof paint.
Any recommendations on a best brand, cheapest price or any to avoid?
Can you mix it with silicon water repellent for extra protection?
Cheers

You could also use Thompsons water seal.
I used it a few years back on a house I had sandblasted and repointed.
Worked well, and after applying it, you could see the water "beeding" on the wall instead of penetrating the stone.

Chris
P.s. quick tip if you buy some - don't bother trying to brush it on.
Buy a cheap garden sprayer (large type with pressure pump on top etc) and use that to spray the walls. Water seal is to thin to brush and if you try, 99% ends up on the floor.

P.P.S. Sorry Mum - now you know why your plants kept dying whilst spraying liquid fetilizer :D