You can learn most of what you need by reading a few books and digging into the forums for specific questions. 

Think of this for what it should be, flipping your "cash".Third, as your cash increases, take some (NOT ALL) of it and invest in cash flow,...the rest keep flipping, repeating steps 1 and 2,...and then 3 again, until you reach your financial goals.REI isn't a series of one time events, it's a system of continuous steps, all leading to a specific financial end result.

The split is very firm specific.

Seek Legal Advice Reach out to a lawyer who can guide you through the specific laws in your area.

Specifically other wholesalers in the area.

I'd love to go over specific properties with you to see if it's feasible.  

The buy box is usually broken down into columns and details the criteria a property must meet to be considered for purchase.

Get some business credits, perhaps amex specifically. 

It comes down to setting expectations; did any of the applicants provide specific, detailed reasoning for backing out? 

Knowing what's "not a good deal" or finding out what they do NOT like, is just as important as finding a "good deal" and having a specific buy box.