Arjen: That is quite a list there !!
I stumbled through them & IF I were to lean in the direction of any of them the 80 Pearson would be my first consideration. The fact that it was used in "fresh water" for most of it's past life is a +.
The Columbia 31.5 looks to be a engine problem just waiting for a new "sucker" ! ADD 10K
27'Cal: The o/b would be one of my concerns as that transon wasn't designed to carry the weight of a BOUNCING outboard in a rough sea !
31.5 Hughes: Again you have the outboard issue + the pictures are 5 years old !!
30 Pearson: ? OK & it has some amenities that you will find handy. I'd look real close for leaks & blisters !!
Watkins 27: Nice size for two people + the survey is only three months old ! Look it over & talk with the marina that did the work.
78 Columbia: !!! Look at the rot in the bulkheads where the chain plater are anchored ! The bolts are pulling through as we speak !!
Cal 27: My first question is what are you going to do when that rowboat slams into you in rough seas ? I mean other that sink !!
I guess looking at all of the listings the 80 Pearson or the 27' Watking should be looked at. Your "dream" of cheap living cost in other countries is appealing BUT remember even with a 6K $ boat you would appear RICH to the people that live there & poor to the tourist that sail there. Do you have any personal protection on board as you will surely need it some dark night when your dingy & outboard are carried away by some hungry local !!
Just my personal thoughts, but you asked so ther you are. Good Luck.
ps: I got back home from Florida yesterday, sorry I missed you. Shon