I might even fix up the electrical enough to get power up, since I can do all that, and the cost of materials is next to nil, and that will enable me to run fans to air out the property, power tools to do the "puttering around," etc.2) If that fails to make it attractive enough for a cash buyer, offer the best terms possible to minimize the rehabber's out-of-pocket expenses and facilitate the easiest deal.

I would request that she provide a 30 day notice, then i would ask that she keep the place clean and facilitate showings.

No LLC means better vesting for you and facilitates refinancing. 

Take into account you have to pay insurance and a general power bill, have someone who collects rent and facilitates move ins but still the number could still produce some serious cash flow.

About the 3% being credited to the buyer: As long as there is "appraised value" to facilitate an offer that the seller will accept that will "net" them an amount they would have accepted with out the credit, then it's splitting hairs.  

I disagree with Matt, an Agent is there to facilitate the purchase they are not contractors; I believe Buyers make mistakes by relying too heavily on Agents when it comes to important decisions beyond market pricing & research. 

In the past a centralized entity was tasked with facilitating the record keeping.  

This last one is more specific to my situation: Should I allow the tenants to market online (ie Zillow) for new tenants or should I take on that responsibility and give the tenants the responsibility of facilitating the tour etc.

When setting up a seller-financed deal, is it usually recommended to use a real estate agent to facilitate the deal?

Your agent should guide you on the next steps to take and should facilitate much of this for you.