And by 'affordable', I mean ideally, under £50 in the sales, though obviously that might net me a bargain at the moment. I noticed that there are a lot of heavily reduced waterproofs in the end-of-summer (wahh!) sales in outdoor shops. Am going to Go Outdoors tomorrow. I think I need the equivalent of a gastric band on my wallet. 
I know nothing of the leading brands (except that they're famous names) and have very little idea of what I'm buying - I'm very much a fair weather walker but need something sturdier than a Kag in a Bag (which is all I seem to have at the moment for rain) and ideally would like something lightweight enough to slip on over a t-shirt but also to wear during downpours the rest of the year, over jumpers/fleece, etc. Nice colours would be a bonus, as am fed up of all my coats being charcoal/black/brown/navy. 
Thanks for any help or tips!