I had BlueJacket AwlGripped in Grenada at the Spice Island marina and
couldn't have been happier with the work. BlueJacket is 40' and the
cost was about $6K. They did a super job. The owner, Junior, kept us
well informed on the progress and kept the job on schedule. English is
spoken there. Here's a photo of the job:

http://www.geoffschultz.org/200
_Sailing/VE_Los_Roques/imagepages/image2.htm

I've also had a fair amount of work done in Fronteras, Guatemala which
is on the Rio Dulce. There are 2 American's (Chris and Pat) there who
run a business named "The Shop" ( http://www.riodulce.org ) who do just
about anything at very reasonable prices and their work is very good.
When they do the work, it's $25/hr, but when the locals who work for
them do the work, it's $3/hr. The locals tend to do lots of the
painting and varnishing work and do a very good job. I can strongly
recommend them. They send regular progress reports and attach digital
photos of their progress.

The biggest problem in having work done in these places is getting parts
and supplies into them. Things just aren't readibly available. Plus
when you bring things into Guatemala you pay a 30% duty tax. If you
know what you're going to need, you can bring it with you, but if you
forgot something...The closest real place to buy supplies is in
Guatemala City, which is 4+ hours away. The Shop does have someone who
buys things for them there and places them on a bus.

For this exact reason I moved BlueJacket to Ft. Lauderdale this past
spring to do major work on the boat. I was installing a new generator,
wind generator, different davits, solar panels, a hard dodger,
electronics, etc, etc and I knew that trying to get this done down there
would be next to impossible. Plus I was doing a lot of the work myself.
As it was the car could almost drive itself to the marine stores and
Home Depot.

As is almost always the case, there are plusses and minuses to
everything. If you're going to have work done in far away places, then
you have to absorb the transportation costs too. Best of luck making
your decisions!

-- Geoff