Time and unpreparedness sharply and gradually cut into this margin.

My threshold is 27% per property is left in the bank as contingency (9% for vacancy, repairs, and capex) My property manager takes her cut before the funds go into my account so I don't have to worry about budgeting that.

Whether it's because you can't find an investor-friendly realtor or the MLS and craigslist just isn't cutting it. 

Other wholesaling tips greatly appreciated, I have already been cut out of one deal and attempted to be cut out of another.

Like LASER focused on what you want to specialize in.

That said, many GCs don't want to work for so little money (compared to working for the typical home owner) and many investors burn out their GCs by trying to get them to cut corners and do things cheaper, just so the investor can make more money.

Outsourcing to a company you have no direct control of is just not going to cut it.

@Paulo AscurraWhat Mark failed to mention with his cut-n-paste greeting is that much of the content in those blogs is US-biased.  

Him and his team do not cut corners.

Here  in NC that goes through small claims court and they are fairly cut and dry so they are pretty smooth once you get in front of the judge.