Yes, terrible idea. Left in salt water the boat will be destroyed in no time. In your case outboards are the only way to go.

I'd make sure you had someone over there that wants to work on Mercury I/O stuff.

Here is a lift alternative:
http://fabdock.com/

Pretty cool set up, the concept isn't a lot different than all the lifts at LOTO, except the poly tanks there are literally bullet proof depending on the caliber of the bullet.

Completely understand your situation , it's exactly the same out here. No end of the day haul out facilities , no recreational/private trailering and very salty water .
I already know the answer , but ask the locals how they deal with it . Oh , and then there's that little problem of being in hurricane alley that means you have to have a plan to stash the boat in a hurry somewhere safe . One thing about the o/b option is that at least you can tilt them out of the water but the salt is always there , regardless.
Salt is anathema to most folks on this site but some of us have no choice .

Just got back from puerto rico and the us virgins, outboards are the only way to go in the islands apparently, sport fish or center console with some kind of sun cover makes perfect sense.

99% of salt water boats are outboards and center consoles.

You'll have a pile of junk in no time if it sits in the salt...either get a lift or look at a CC w/outboards. Donzi's new 41GT is for sale with twin 400's.