If you want to add Yohimbe HCL to make it more effecitve you can do it with SNS Yohimbe 2.5mg caps. Cheap and awesome IMO.
To calculate max Yohimbe for you: .2mg/KG of BW , so do your math , and split it in 3 doses, do NOT exceed 15mg (anyhow I doubt you are that big for that dosage) Build up a tolerance for it, if not you will regret it, use the same scheme presented in the aforementioned link. Think of it like this:
1Y=5mg Yohimbe HCL , so work your way up in the scheme presented with 1/2 Y like they do with 1/2 caffeine and 1/2 ephedrine.
Lean Extreme is a great add, just remember, no need to go all out on leaning out your wallet, fat loss is mainly dieting efficiently and training hard !