Here is the video of the first successful test of the two lift cylinders lifting the front of my car.  Not sure what those two lavender lines are in the video.  They weren't there when I took still pictures with the same camera.  It's a really old camera.

I've decided to become an inventor attempt to fulfill the need to store your small power boat out of the water while it isn't being used.  No more pounding and bumping against the dock with every wave or blast from the wind.  Think about the money and time you'll save by not having to constantly clean your boats bottom to eliminate marine growth.  And more money to be saved with lower fuel consumption by always having your boat's bottom free of barnacles and other growth.  And all you need is a garden hose to do the heavy lifting. 

Below are images of my first two test cylinders and a video showing that with only about 40psi water pressure from a common garden hose I was able to lift the front of my car two feet into the air.  This car weighs approximately 3500 lbs. and since a large percentage of the weight is up front, I estimate that the two cylinders combined to lift approximately 2200 lbs.  Four cylinders connected to the four corners of a boat cradle would be more than adequate to lift a 25 foot open boat and motor. 

Component pictures:

Video of the lift test using two hydraulic cylinders attached to a cradle to lift my car.

Here is a video of the first "dry" test of the boat lift just outside the building my shop is located in.  It was mostly successful, but revealed a couple of issue that I am addressing and will produce a better product.  And, again, please excuse the shirtless me.  But it was pretty warm (well it's always warm here in Bocas del Toro).  Eat your hearts out Northlanders.  :-)