my cats hair loss.

Question
I have a male cat, Joey, who is about 5 yrs old. He is spayed and is kept indoors except for the occasional times that he slips outdoors, which is not often, and he has always returned unharmed and hungry.
For the past two to three months he has been licking and biting obsessivly starting on his stomach/ rear hind quarters. At times I thought it was getting better, but his hair is now getting more and more sparse in this area. I am also able to feel a couple of scabs along his back, towards his tail. He licks himself and the hair is all over the floor in his favorite places. He seems healthy other than this. I am laid off my job, a single parent with three children at home, so it will be very difficult to take him to the vet at this time.
Is there anything I can do to help him. I don't see any evidence of him havimg fleas, as he sleeps in our beds and no one else has had any bites or anything like that.His hair on the stomach side and down his back legs is very very sparse and his skin is showing through. This seems so strange since he has such a thick coat of black fur.
Thank you so much for your time and you input.

Answer
You have described in textbook terms what happens to a cat that is allergic.  They "barber" off the hair along the belly and thighs and their skin develops crusty areas over the neck and base of the tail.  This is fairly easy to treat with a shot of a long acting steroid called DepoMedrol.  Ask your vet about that.  It should not be that expensive.