tricky — I’m going thru the same search as I am putting the condo on the market. I checked the Forum for recs and Paint the Town got the most votes. They are right here in WS. I don’t feel comfortable revealing their bid as it depends on sq. ft., number of coats, quality of paint and any idiosyncracies about your place. My place will require 2 coats, possibly need primer in one room and involves 2 bathrooms, 5 closets and pantries, etc. since I am selling. I think my place is 1200 sq. ft.
I would guess you’d pay anywhere from $2k to $4k. You can save money by not having them do closets, etc. They will do an estimate and they do accept credit cards. Good luck.
http://paintthetownseattle.com/