I should have mentioned several alternatives...hydraulic lifts may be the penultimate, but not likely required unless you have an awful big tender....and other hydraulic uses aboard....an electric winch is most common....consider dc vs ac....nothing wrong with using a hand trailer winch...that's what I do as I did NOT want to rely on any electric power...
Also, in general, the least expensive winches/lifts are those made for docks and pilings....often galvanized,for example, rather than stainless/powdercoated/ or whatever....sounds like that's what becky posted for his lightweight application....heavy units go thru the deck for support below on a bulkhead