I purchased 2 lifts from Sun stream. The one attached to my dock shifted over the first year torqueing my dock. My sunstream repair man said it was a problem with my dock. I had a dock repair man come out and supported the lift with a bracket. He said it was not installed with enough support. This added $ 1000 to the price of my lift. Sunstream does not support their product with service. Beware of added cost.