Border Collie Hair Loss

Question
For about two years now since we've moved to San Antonio TX, our 7 year old Border Collie has been losing a lot of hair, mostly due to her scratching and biting at her coat a lot, she basically rips her hair out and sometimes ends up causing wounds on her skin that bleed. She loses the majority of it around her hind area, above the tail to the middle of the back, her entire tail, and her lower hind legs. A few weeks ago it got really bad and it spread nearly to her whole body. After that we found a shampoo that's hypoallergenic and supposedly stops itching, then we used a conditioner to accompany it and started feeding her fish oil tablets and a diet with a lot of meat in it and so far it has worked wonders on her, she grew back almost all her hair in two weeks. I gave her a bath again with the same shampoo and used the conditioner afterwards since it says you should do so every 1-2 weeks, and the diets still going, so it's only a matter of time to see if it'll continue to work. We also noticed a few months back that she has a lot of flakes, and it's extremely tough to get them out, none of our dog brushes will do and we end up having to sit her down every day or so to pick out the flakes. We might be able to take her into the vet soon to have her checked up on, but money is limited nowadays. If you have any suggestions of what it could be or what we could do, that would be extremely helpful and very appreciated!

Answer
You are describing classic flea allergy dermatitis, which affects the lower back and rump area.  There may also be a secondary bacterial infection.  Keep on doing what you are doing if it seems to help, but your vet may be able to help with medication to keep the skin from over reacting and something to help control infection on the skin.