There are more pros than cons when staining a deck. Deck stain is more affordable than paint, it protects the wood and allows the natural textures to shine through, and it can revive the appearance of your home. However, deck stain also requires prep work (sometimes days or more), carries more upkeep than a painted deck, and can fade over time if not cared for. 

The staining or painting process involves cleaning the deck, sanding surfaces, applying a primer (if needed), and carefully applying stain or paint for an even, lasting finish.

There’s no single paint that’s the most waterproof. Instead, there are several types of waterproof and water-resistant paints that suit different purposes. Epoxy paint, for instance, is commonly used to provide a waterproof coating to floors and decks. Masonry paint is an excellent choice for exterior walls. Meanwhile, there are waterproof acrylic paints that can be used for interior and exterior walls. It’s more about choosing the best type for what you’re painting instead of the most waterproof paint overall.

Deciding whether to stain or paint a pool deck depends on your budget, desired look, and the deck's material. Both options can work. Paint offers a wider variety of color options, provides excellent water resistance, and can last longer. However, it requires a primer and can eventually fade or peel. Stain is often cheaper, easier to apply, and penetrates the wood for a more natural look and longer-lasting finish. It also has great water resistance. The downsides are fewer color options and the need for a sealant. The choice can also depend on the deck material; for example, staining may be a better option for concrete as it bonds well and lasts longer than paint.