I am interested in the wholesale part of the real estate niche as I have bad credit and no money but I also am a law abiding citizen. 

Overdraft is basically a line of credit attached to the account. 

My tenants have to sign the lease and give me the security deposit with 3 days of passing credit and background checks.  

The most common way to reduce closing costs is to have offered $Xk more for the property, and ask the seller for $Xk in seller credits towards closing costs, or just get the seller to pay for certain line items. 

@Franky Juwana, I don't think you'll like my answer, but here it is: you're looking at a terrible market for real estate investing in terms of cash flow return.  

Treat it like a line of credit, the amount will obviously be rising.

We parlayed up until we have a nice, paid for home and now use the line of credit on it to buy flips.

I have excellent credit but no money for a deposit. 

The only credit I gave him is for the floor but I shouldn't have done that.

It really should be recorded but we are a little more loosey goosey with things since it is a line of credit and is paid on direct draws.