By the early 1990s, Rwanda, a small country with an overwhelmingly agricultural economy, had one of the highest population densities in Africa. About 85 percent of its population is Hutu; the rest is Tutsi, along with a small number of Twa, a Pygmy group who were the original inhabitants of Rwanda.
1 Power sanding, stain and seal â This is a very aggressive procedure normally used on decks that have not been well kept or are changing color. The average cost is $2 to $4 per square foot.  Light sanding, stain and seal â This is a general annual treatment for a deck.
In fact, as you can see on our cement patio cost guide, you can stain your cement patio as well. Depending on the color or design, staining can add an extra $4/sf to $10/sf. Finally, cement is a very popular choice for pool decks. While wood gained some steam over the year, cement and concrete remain the gold standard for backyard surfaces (other than grass).