JHO
Flying here with EASA/JAR or any ICAO licence is straightforward.
There are two types of aircraft here (ignoring the UK registered microlight) either N or 8P, 8P being Barbados registered.
Fundamentally you are looking at the two out of three rule - So Barbados Airspace, Barbados Licence, Barbados Airplane - you need to be two of those to be "legal".
You can fly 8P airplanes solo in Barbados airspace with any ICAO licence so trips around the island; two out of three - Airspace and Airplane.
You cannot fly an 8P to say St. Lucia - Barbados Airplane, St Lucia Airspace, UK licence
You can't fly an N registered airplane anywhere as all three are different.
If you want to fly 8P turn up and fly - there is usually a minimum 30 minute check out if you have time logged - the problem may be insurance requirement if you have no time on type.
So Coconut Airways (yes, like the song!) they have a PA38 (Tomahawk) on 8P and also a PA28R (Arrow) a complex also on 8P together with a PA28 (Archer II) on the US register, the microlight is UK registered but not rented solo. In addition likely to be on the line soon the Barbados Light Aeroplane club have a Cessna 152 on 8P.
Now clearly for most pilots with a PPL the Arrow is likely to be out for solo as unlikely to have time and who wants to do extended checkout for insurance (5 + hours).
The Tomahawk and the 152 are not exactly going to cut it if you want to take family or more than one passenger - but are perfect if you're on your own or with one other person.
If you want to go to another island solo that cannot happen with your licence - you can of course go with an instructor - but he'll be taking up a place and the best passenger seat at that!
If you want to fly the Archer you will need an FAA PPL - if you search for 'FAA piggy back license' on Google you'll find out how to do that - it is a little complicated but you don't need a separate US medical. Any ICAO licence holder can get one but for it to be valid your original ICAO licence must be valid, so medical and flight review current AND you MUST also have a current FAA flight review (there are FAA instructors in the UK that can do it, or there is one here who can do it) - certainly worth doing as no matter where one goes there always seems to be US airplanes for rent.
The cost US$1=B$2 - PA38 and C152 = B$280; Archer II = B$400; Arrow = B$450 so cheaper than the UK availability is generally very good - the Tomahawk and Archer get most use at present but there is never a day when the airplanes are booked solid (look on coconut-airways.com and you'll see what I mean) there are in effect only five active private pilot here (the word is active meaning - not a person who flys once a year to keep their licence!) this means that taking a four place plane away for days on end is not a big issue and the daily minimums are very low (put five hours on it in a week that sort of thing)
To declare an interest I own the Archer - it's not cosmetically good (soon to be refurb'd once the new Coconut Airways hand is up) but it has a low time engine, an altitude hold a/p (very good for long over water flights), IFR certified, jackets, a four man raft and a water proof GPS locator beacon - search for N75276 on youtube and there is a video that some guys who rented it earlier this year made - their first song is rather good too