GetMyBoat provides private owners and commercial operators with sample rental agreements for boats, houseboats, and personal watercraft (jet skis). Because they are only templates, consult with your lawyer or legal counsel and review the documents to make sure they cover your specific needs and terms. It is also a good idea to create a pre-rental checklist in order to walk the renter through the particulars of your boat.  

Rental Agreement for Boats

Boat Rental Agreement Samples

Rental Agreement for Houseboats

https://getmyboat.com/boat-rentals/united-states/washington/kettle-falls/elite-houseboat-on-lake-roosevelt-2412 

Rental Agreement for Personal Watercraft

Boat Rental Agreement Samples