Water views are some of the most difficult factors to value when pricing a home. There are so many contributing factors to a water view's value, it's hard to know where to start. Everything from the body of water, direction, angle of view, fullness of view, proximity to water, obstructions, reflection, which rooms have view/which don't, and potential of future development/obstructions can weigh into a water view's value.
There's no perfect way to calculate the value, but there's also no denying that there is great inherent value in a water view. The most straight-forward analysis involves condos, as they typically have a view from only one side of the home, and it usually doesn't require standing on a roof/opening a bathroom window/walking to the end of a lot as is required in some single family home views.
Although these numbers by no means give a standard for the valuation of water views, it's interesting to see the differences in sales prices that can be somewhat attributed to the view. In 2008, there were over 2100 condos sold in the city of Seattle. Out of those, about 700 had a water view and 1400 did not. Considering those numbers alone, it's likely that many of these sellers had "peekaboo" or very minor views of the water, as it's unlikely 1 out of every 3 Seattle condos has a true water view.
Miniscule views notwithstanding, water view condos had a median sales price in 2008 of over 40% higher than condos without a water view. The median sales price of non-view condos was $277,000 while water view condos sold at a median of $392,500. Days on market was similar between the groups, at just about 7 weeks for all condos.
Clearly there are other factors at work. A building that will have water views will likely be built to a higher standard than one built on inexpensive land elsewhere. Water view condo buildings would likely build a higher percentage of 2 and 3 bedroom condos, as they're planning on more upscale buyers. This too, would skew the median price upward.
With all of these factors involved, it's still clear that water views have great value to a home buyer. Each individual home's view value is probably much more personal to the buyer than can be pinned down with a formula.
Statistics not compiled or published by the Northwest Multiple Listing Service.