Well you already have great info above on the cost of living so I won't go into that...but having lived in Seattle most of my life, I have to say it is beautiful. You have it all here...lakes, ocean, mountains and of course rain!!!
All of this within a short drive. Vancouver is an easy drive from the Seattle area and takes about 1 1/2 to 2 hours.
If you have any specific questions about this area, I would be more than happy to answer them.