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.
Expect to pay approximately $2 to $4 per square foot for concrete staining that involves application of one stain color and protective sealant. Stain projects can also expand to include border designs, stenciling, and multiple colors, which can increase the price to $15 per square foot.