I have Regatta quick dry walking trousers. They have been very good and only cost £25. I also have a soft-shell that I got off eBay for £11 and it's actually quite a decent piece of kit for the price. Shower proof, very good at insulating too. My bas layers are also Regatta and do the job adequately and cost less than a tenner each.
Of course they aren't going to be the best stuff out there, bit frankly for doing a bit of walking in the summer in the UK you don't have to spend hundreds of pounds on technical clothing IMO. You can if you want of course.
It wasn't that long ago AW was wandering about the Lake District in a tweed suit.
Having said all that, I have left my Regatta boots behind and now wear 3/4 season Berghaus boots.