I'm very happy using a hardtail on the trails here in Oregon, but I've never ridden a bike with full suspension nor have I ever used disc brakes. Some full suspension bikes are heavy.

I've seen some good deals on craigslist every once in awhile - especially older bikes. 1st priority is the right size frame. A close second is the frame quality. 3rd is the wheels, 4th is the components. I just saw a USA made Klein with Deore XT components for $200 posted a couple days ago - I checked today and it's been sold. It might be harder to find a low priced mtb on CL in the Seattle area.

I know you're asking for info on new bikes, but I'd still peruse the bikes on CL in your area. Be sure to noticed the condition of the shocks, they may need replacement.