HCG is quite pricey when compared to what it should be. Should be about $10 per 5000iu....and that's for the black market. HCG is the easiest thing to test for authenticity (or counterfeit) and this might have something to with its relative rarity when everything else is so readily available.
If you actually have a prescription, Freedom Fertility sells it quite cheap. And if you have insurance, then you can get as many vials as the Rx says for the month for fifteen bucks!