Just my 2 pennies but I think he would be better off buying known/named frags and growing them out. Then fragging and selling/trading for more frags to grow out and do the same.
I say this as I was just thinking about starting a thread illustrating how I started with a few jawbreakers a couple of years ago and have since flipped them into over 75 different types of corals including many high end sps. I'm not really even a fan of mushrooms myself, but I knew I could grow them quickly and that there is always a decent demand for jawbreakers. It has worked out far better than I ever imagined.