None of the boats you listed can carry four adults very well. Your choices should really include one the the original Maincat 20's or a Farrier designed Tramp, Super Tramp or Eagle trimaran
. They will cost you less than $15000 on a trailer, and can be beached easily, but aren't that easy to launch from a beach. You'll need a ramp
Bill Gow is right about the stilettos. They made a 23 than might sail ok with four people, and the Hobie Cruiser 21 could probably do it to; its the one boat that could be easily beach launched, can carry camping equipment
and a small motor
, and its sail can be lowered while you are in deep water.