This would be your own personal transaction. The FAQ over on the rental board give you some guidelines. It's totally up to you how you want to handle it and what type of restrictions will be on the rental. Things to keep in mind, will you offer any money back and/or offer to rebook if the renter wants to make a change or needs to cancel? What about the dining program and/or Magical Express -- will you make those arrangements for them. How often will you be willing to make changes? How will you get payment? All at once non-refundable? Half before booking, half at some other point?
Know what you are willing to do and have your price point in mind. I'd put it all down in writing. Not sure how "legally binding" it would be but it's best to clearly state the terms up front.