you can also raid your local vets for any free Hills or Royal Canin samples
my Feral/Stray (we are not really sure) kitty Mabel is on the boxes of Tesco Premium and she is doing fine, I also feed all 3 cats (indoor two and Mabel, you can see em in my signature) Tescos Premium pouches as £2.40 for 12 (and a special offer 24 for £4.04 at moment) which even Indy who is picky about his wet food will eat
Also check out your local Bargain Madness (BM) if you have one, in some stores they have Active Fit and Schmusy pouches at a big discount, both are premium wet food at 14% meat. Schmusy at 6 for £0.99 and Active Fit at 4 for £0.89. They can often carry other high quality brands for low prices
Being out of work I know how hard it is affording the best quality foods I can find but also affording me! so a bit of shopping around can help, keep an eye out for special offers and if that means a stupidly large amount of dry food... you can always freeze some to keep it fresh