Based on what I read here, I decided to mix up different solutions for maximum effectiveness.
I used ACV, Yeast and Sea salt (about 2 tbsp acv, 2tbsp yeast and 1tbsp sea salt) in 500 mL spray bottle, and used on my cat once a day. It was dramatically effective!! My cat stopped itching herself all the time and was flea free, but we didnt take care of the eggs so she became re infected... we will re-do the treatment with eggs in mind soon.
Interesting side effects is that her hair became completely nice and soft, and prior to that had been filled with hard hairballs all of her life! She also got a very improved mood, more energy, and became more sociable!
I believe the nutrients from the high quality Brewer Yeast (used Lewis Labs brand), and the ACV did wonders for her health! As soon as she would be all wet with the mix she would try to lick it all up, so she ended up eating quite a bit of it... (a reason why NOT to put too much salt in there..)