Did you Know that Washington is a Community Property State?
This means that you can't buy real estate in Washington State without addressing the spousal interest. Be sure to ask the buyers what their marital status is and write it in after their names on line #2 of the Purchase & Sale Agreement.
This is especially true If there is institutional financing involved. If the buyers have all cash and really don't want to deal with it, then title will create a special exception to their policy of title insurance, "Right, Title & Interest of the buyers spouse" which will likely be no fun to clear when they go to sell the property.
Don't hesitate to call with any questions,