This home is not far from the beach and Florida of course is humid. When constructing the cabinet material choice is an important consideration. Big box cabinets are typically particle board covered in paper i.e. a sponge. They come in standard sizes and limit your choices. Since remodeling is a major financial decision a little extra cost in material and flexibility in design, having a local cabinet maker construct your cabinets will make your investment last.
This cabinet is fabricated from a good quality plywood. The edges and the unseen surfaces are sealed with primer. The interior of this cabinet was laminated with countertop laminate. This will serve to protect it from the humidity of Florida as well as any leaks or spills that can occur. I try to do this with any cabinet that will have plumbing or sinks in them. In our Craftsman bath vanity we skipped the laminate but did seal all surfaces with primer and paint.