The difference between a 3-year paint job and a 7-year one is rarely the color on the cubeta.
Quick answer: near the Guanacaste coast, the paint system that lasts is alkaline-resistant sealer + 100% acrylic with high UV resistance, upgraded to elastomeric on walls that take direct sun and salt spray. Interior problem areas get anti-mold lines. The paint itself matters less than most people think — and the sealer matters far more.
Walk any beach town in Guanacaste and you'll see the same wall twice: one house chalky, stained and peeling at the base after three years; the neighbor still crisp after seven. Same climate, same sun. The difference is almost never the color brand on the cubeta — it's the system underneath it.
Concrete block and stucco — which is nearly every wall in the province — are alkaline and porous. Paint applied directly onto them gets attacked chemically from behind while moisture moves freely through the wall. An alkaline-resistant sealer (sellador) closes the pores and buffers the chemistry, and it's the step most often skipped on cheap jobs because it's invisible in the final photo. If you compare two quotes and one is suspiciously cheaper, ask both what sealer they're using. The silence will tell you what you need to know.
For most exteriors, a quality 100% acrylic from the lines sold here — Sur's premium ranges, Lanco, Protecto, Sherwin-Williams — over proper prep is the right call. Within roughly 2 km of the ocean, or on walls with hairline cracking, elastomeric coatings earn their 15–25% premium: they stretch over movement cracks, shed wind-driven rain, and shrug off salt spray that eats standard films. Roofs are their own category: zinc wants rust converter plus a heat-reflective roof coating — the interior temperature drop is noticeable the first afternoon.
Green-season humidity turns bathroom ceilings, closet walls and any closed-up room into mold farms. The fix is part ventilation, part chemistry: kill the existing mold properly (not just wipe it), fix the moisture source where there is one, and repaint with a fungicidal (anti-hongos) line. Standard paint over mold is a two-month fix; done properly it holds for years.
Not sure what your walls need? Send us photos — we'll tell you honestly whether you're looking at a wash, a repaint, or a repair-first situation, and quote it in writing either way.
A 100% acrylic with high UV resistance over an alkaline-resistant sealer — or an elastomeric coating on the most exposed walls. Locally, the premium lines from Sur, Lanco and Sherwin-Williams all offer suitable products.
Salitre is salt and mineral efflorescence — moisture inside the wall carrying salts to the surface, where they crystallize and push paint off. Paint alone can't fix it: the wall needs the moisture source addressed, the salts brushed off and neutralized, and a sealer before repainting.
On green-season problem areas — bathroom ceilings, shaded north walls, closed-up bedrooms — yes, a fungicidal additive or anti-mold line is worth it. It doesn't replace fixing ventilation and moisture, but it slows regrowth significantly.