Costa Rica

So some of you may remember my FH and his friends have crazy destination bachelor parties (last one was in Colombia). I've resigned myself to this fact and I'm excited for him about his which will be at the end of September.

Now here's the problem. He had his heart set on Costa Rica but apparently it rains like 24/7 there in September. He's looking to rent a house with multiple bedrooms and have like a cook, butler etc (its much cheaper and more common than it sounds). Does anyone know of any countries/islands that are similar to Costa Rica in activities and climate (when its not raining) that we could look at???

I feel so bad for him, he totally had his heart set on this!!!!!

Thanks for any input you could give!

Tell him to check out Belize...similar but it won't be as rainy i don't think.