The first time we did it, we had the other sides of the shower wall studs all exposed, ran the shower for several hours to watch for any signs of moisture, and saw nothing. 

The water will take the path of least resistence, and take up residence in the exposed underlayment and subfloor.Here's how I prep for setting a toilet...1.

Your agent should know the most likely disqualifiers- missing carpet, holes in walls, exposed wiring, etc.

In all likelihood, flipping 1-2 homes per year with such a plan, considering that you are also personally flipping so many homes would expose the gains on those flips to UBIT taxation.  

Primarily because they were not exposed to the market.

Hence the generic “proof of funds” nonsense letters you download off the lender website and fill in yourself; the obscure “business or financial partner” who needs to “approve” the purchase; and the “exclusive list of buyers” that only the wholesaler has access to and will expose the seller’s property to if only he agrees to sign a purchase contract obligating him to everything and obligating the wholesaler to nothing.  

These heavy regulations are a direct result of an exposé the Seattle Times did on the industry a couple of years ago.

Are they doing everything they can to expose properties to the widest possible market?

If your property isn't there, its only getting exposed to the small fraction of buyers who look in other places.

I do impose limits on myself as to how much cash I want to have tied up at any one time.My first deal had a self imposed limit of exposing no more than $40k of my own money.