I closed on a small finca 5 weeks ago. Things I wish I'd known:

1. The road access matters more than the view. A finca you can't reach in rainy season isn't a finca, it's a hobby.
2. Water source first, everything else second. Spring, well, or municipal? Get the answer in writing.
3. The neighbors matter. Talk to them BEFORE you buy. Once.
4. Property history. Pay for a proper title search. I almost didn't and the previous transfer had a hole in it.
5. You will spend more than you budget on the first month of fixes. Plan for it.