I was originally hired as a software gopher - my first few weeks were running around with a stack of "floppy" disks to install Word on machines. Then my boss was like "Do you know about this World Wide Web?" (it was almost always said like that - you could hear the caps) and I responded "yeah, it's ftp with pictures, a waste of bandwidth and a passing fad!" He said "We're shutting down our mainframe bulletin board, and while we have email now, we need a replacement for announcements. We'll bump you to $8/hr" and I said "yes!".
I've been in webdev since, though it did take a few more years for my assessments to be more accurate :) (Me in 2000: "Javascript isn't even a language and no serious developer would use it". Me today: "Javascript has been my primary language for 6 years and that doesn't look to change soon")
COL in Seattle: There's no state income tax, but the sales tax (varies by locality) is about 10%. That's usually a good assessment of most prices (10% higher than I saw in Richmond) other than housing, which has been crazy. I moved here in 2012 and grabbed a 1 bedroom apt for $900/mo - that's probably $1000 - $1200 now (web shows prices as unavailable). I bought a small house in a not-great-but-not-terrible area for $291k in 2013 and it's now worth (according to my insurance company) twice that while the neighborhood has gone downhill. We're looking at moving, but prices elsewhere have shot up even more - if we don't want a bigger commute, we're looking at houses that are painfully close to or beyond $1 mil, which breaks my brain. Then again, we're picky and don't want a duplex, and our house is from 1951 while others are much more modern.
A lot depends on which area you live and work in - I live in Shoreline (used to be "North Seattle") and work in Downtown, and my experiences will be very different than people that are in Bellevue (East of Seattle) or West Seattle, but I can't say how. Many of my coworkers and friends take a longer commute in exchange for getting great homes in good neighborhoods in areas like Issaquah and Sammamish.
Overall I love Seattle and have no desire to leave at all, but prices are higher. A friend moved out here that worked as a restaurant manager and moved away again because the prices were too much for him both personally and in terms of his store (most places have a $15 min wage, which I support but definitely places challenges to some existing business models). That said, he was here for 3 years, got married, and had a kid, so he had plenty of time to weigh his decisions, he wasn't priced out immediately. He also moved to a more remote area (Marysville is well outside even the Greater Seattle Area) after the first 2 years.
If you're interested I think it's worth applying to some places - I was living in VA when I applied and they flew me out so I got to see the city and pass through some stores with no commitment besides being serious in considering.
Tip: Seattle in June is a very different thing from Seattle in November. Seattle DOES spend a lot of time overcast, but it turns out they have more sunny days than, say, my hometown in PA, and when they talk about "overcast" or "rain", it isn't the same meaning as what I called "overcast" or "rain" on the East Coast.