There is nothing worse then getting stuck because you can’t execute the plan.  

I understand that typically a portion fo the fee is paid on execution of the assignment contract with the balance at closing, but to get this transaction to work the wholesaler will be paid his fee at closing.We could do a double-close but we threw this out as an option to the wholesaler to put a little more money in his pocket and save his portion of the buyer/seller closing fees on the AB side of the transaction.Any direction would be appreciated.

Conceptually very simple, yet clearly nuanced and detailed in the execution.

You are going to have a bunch of headaches qualifying and some more during the execution depending on how extensive is the project. 

A general overview of how to evaluate if bringing in homes will work for your park and then how to execute.

Not sure how it is in the USA, but minor's cannot execute a contract so you would need to be 21. 

Additionally, what if the owner of the home does move out, and the assignment contract is not executed?

Typically they'll have an attorney that runs the office or is on staff.

As @David M. mentioned above, executed leases will go a long way. 

Take your time planning & executing.