Building a Hoist For Your Hobie

Recently someone gave me a Hobie 14Turbo. I have a u shaped dock at the back of my house where I keep my ski boat (fresh water). I would like to keep the Hobie in the water also. How would one keep a Hobie on floatation? I have extra floatation as I just rebuilt my dock. There must be a way to keep the Hobie next to my dock out of the water. So I need some ideas on how to design/build a hoist/float to keep the Hobie out of the water. Even though this is fresh water when someone leaves their ski boat in the water for a significant time they have a real problem with discoloring the hull. Any suggestions would be very helpful?
Thanks,
George

How deep is the water?

A lot of people build "H" shaped frames out of gavlanized pipe and drive them into the bottom until the crosspiece is a few inches above the water.

Two frames are required to support the boat.

A length of PVC pipe on the crossmember acts like a roller and protects the hulls.

You can practically sail the boat up on to it, then tie it down.

This guy had a similar system, but done with 4x4's between two docks (scroll about halfway down on the page):

http://www.jaimezx.com/Boating/Hobie/part5.html