This means that the average home, containing around 200 feet of gutters will require at least 6 downspout installations. According to the website for Better Homes and Gardens the pricing on downspouts will range from 9.70 to $10.20 for galvanized steel, $4.80 to $7 for aluminum, and $5 to $8 for vinyl.he prices quoted are for the purchase of materials by the DIY homeowner, and when a professional gutter company is hired to tackle the job the prices will tend to increase only marginally. For instance, aluminum downspouts being installed by a gutter company will usually require around $8 each.