Some marinas will lift off a trailer with their forklift. Check into marinas with dry rack storage- they have the big forklifts. Trailer type will determine if they can slide the fork lift right in, or if they have to prop up the boat and use slings.
Is your trailer steel or aluminum? If aluminum, I'd dunk it and rinse it really good when you get home. I only boat in salt water and that's what I do.