The cost for a professional pressure washing company will vary depending on the service that’s needed. Let’s consider the factors that contribute to the cost: what area you want washed (deck, walkway, fence, siding)? How much of the area you want done? And what’s the material? When it comes to material, for example, a home’s siding made of wood will cost more to wash than it would cost to clean vinyl siding, as wood is a more delicate material that will require more time and the use of a scrubber brush so the paint and material remains intact. When it comes to the square footage, the bigger the home, and the taller — the more it will cost.