You're making a mistake if you trust this trainer. Just because someone does something one way and it seems to work ok, doesn't mean that it's the intelligent approach. That prop/water retention explanation... well, what can I say but please do some reading here. Punch in some numbers on roidcalc (website) and look at the levels in your system with a 3 day injection scheme.
Pick up an AI to run on cycle to control bloat (and other estro-related sides), and get a SERM (nolva, torem, clomid) for PCT. Unfortunately, with your bodyfat, an AI could be quite important. Maybe the winny helps out with these sides, maybe not. Winny is kind of funny that way, but you shouldn't be relying on it in that sense. Btw, ideally you should drop 10% or so off of your current bodyfat before cycling, but it's your call obviously.
As for the use of hCG in PCT, many have done it before and many still do, but you're far, far better off using it on cycle at lower doses (250 IU e3d or so, starting a few weeks into the cycle) to prevent your testes from totally shutting down production, than you are to using it as a recovery tool after the fact.
Please read the stickies and some of the proposed cycles in various threads in this forum, and then hit us up with follow up questions.
Oops - just saw that you said start date was May 1. Well, get yourself that SERM asap.