Hey guys,
In the interest of sharing information, I'll post this here versus a PM.
First of all, I have no idea where in Costa Rica the OP is going to be - Caribbean side or Pacific side. And if staying on the Pacific side, are you going to be in the Northern part of the Country (Guanacaste or Nicoya/North), or in the central area (Jaco, Quepos, Herradura), or in the Southern part (Osa, Golfito, Drake Bay, Zancudo)?
Regardless, I would recommend you do plenty of homework before your trip - about what type of charters or backwater guides that are available in the region of the country where you'll be staying. The lion's share of crews will work the inshore/offshore circuit. But you can always find a smaller boat that will be happy to take you up into some of the rivers for the species that you want to target. Now, after saying this, please keep in mind - that there is only so much info and/or backwater fishing crews that you'll be able to find and/or contact via the internet. Your best intel will be found via 'boots on the ground'.
Many of the locals do not advertise on the internet. Many of them are just a 1 or 2 man operation, and it is done by word of mouth. What this means, is that your best bet will be to "personally" scout around the area that you are going to be fishing, and there will always be someone that can recommend a small boat / crew for you. Once this happens, talk to the captain IN PERSON. And chances are that the price will be less (sometimes MUCH less) than you'd find on the internet.
Best of luck and let us know how things turn out.
Mucho Gusto
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