650 to 700 is the going rate for the Sero 126iu kit. Make sure its the real thing. The GH vial should contain a wafer, not all powder. Seromo had a counterfeit problem a while back, that they admit to on their web site.
You need 2 to 3 kits to see proper results.
Of course you need to stack. GH alone will just lean you out. You need insulin, an oral, and plenty of test to see the big changes folks expect when they drop 2000. on GH.