I agree with @Brooklyn McCarty ...Too much money to get in and too many restrictions.

An example of this would be mixing your personal money and LLC money in the same bank account.3.

6 properties over 6 years is impressive.If you continue on this approach, you may be able to do better than 1 property per year if you make more money with your employer and are generating cash-flow from your renttal properties.Why switch strategies if you have something working for you?

If you live in the property there are some great owner-occupy loans available, like FHA or low money down conventional loans.

If it is, and I still want the deal, regardless of all these issues, taking some risk if the deal will close, I will put the money to the wholesaler in escrow with a clause that says, if the deal does not close in 2 weeks, the funds will be returned to the buyer, just to be safe..

I want to pay them a preferred rate of return on their money without giving up equity in the deal. 

I know that I stand to make more money per renovation by just paying for the work, but I'm attracted to the idea of partnering with him for a few reasons.

I'd rather use the money to buy another property(s).....

Although, banks have their place, private money is for a specific purpose and a specific type of investor. 

You're Pushing your potential buyer/buyers to possibly walk away if they can't find solution. more often than not the money you end up missing on, exceeds the 1%-2% coop commission you're trying to save.