Give us some stats, experience, Etc. We need more info.
Yes, he is only 155lbs, but he is 5'4. He probably has a lot of mass to gain before he reaches his genetic potential. GH is not something you should spend your money on.
Take that $500 and buy a big jug of QV enanthate, 3 bottles of QV EQ, Bottle of Liquidex, 5000ius of HCG and, 36 pills of clomid.
Also pick up a couple 5 lbs jugs of protien.
Try this:
Week 1 to 10: 500mg of Enan
Week 1 to 10: 600mg of EQ
Week 1 to 16: .5mg of L-dex EOD
Week 13 to 15: Clomid therapy: 300mg day 1, 100mg next 10, 50mg final 10
Take 500ius of HCG on every other Saturday and Sunday. This will make sure you dont get any testicular atrophy.
This is how you should spend the $700+ dollars you were going to waste on the GH.
GH at those doses will only result in fat lose. You do not need that now. You need to grow!