I use sandtex masonry paint. For old and new patches use sandtex exterior primer and undercover before painting. If old patches are flaky use sandtex masonry stabilizing solution first, then primer, then paint. If old patches are crumbling, remove with chisel and redo with sand/cement mix 4:1. You can add waterproof to the mortar (not essential) and I heard some people use pva with success (I don't). Bear in mind that the new paint will be a different shade of white from what it's there because of the weathering effect. - - - Updated - - - Read instructions for all products before using them.

I agree, Colin. The whole point of most insurance is to pay out to the few who suffer a loss. HB

I agree. It is dangerous for anyone on this site to give sweeping statements such as 'GAP insurance is useless', and I doubt he/she or this site itself would take responsibility for someone acting upon that advice only to suffer a claimable event the following week that ends up costing them £1,000's.