Why not? A knowledgeable and open minded PCP is without a doubt more helpful than your run of the mill endo or urologist as far as TRT is concerned. They mostly care about your health and understand your other health issues. If I had a knowledgeable PCP, I wouldn't hesitate to use him.
Since cost is an issue, you will probably only want to concentrate on the sex hormones. This is not ideal and is shooting in the dark, hoping to hit something, but you have to play the hand you are dealt.
Look at www.privatemdlabs.com or www.lef.org They both offer cheap blood tests where you select the ones you want, pay them, and they send you a lab req that you take to Quest or Labcorp (cant remember which) for the labs. This is discussed in the stickeys.
At your age, you shouldn't have much trouble convincing a switched on PCP to consider TRT for you.
As far as cost of your meds, look around for cheaper options. A vial of T from Costco runs about $60 without insurance. You can get needles on Amazon for pennies. Arimidex/Aromasin and HCG can be sourced from Indian pharmacies at a fraction of the price as the US prices. There are also generics available for Adex that are much cheaper even here in the US.
You've got some work to do and decisions to make.