Welcome to the group (from another new member)!
I agree with the recommendations about connecting with a dealer in the Seattle area. Unless you want to invest the time and effort to figure out what you have, it will be hard to find an individual buyer (or perhaps a donee?) for your collection. Dealers are in the business of sorting through accumulations of stamps and making recommendations about next steps.
In my limited experience, the stamp collections available on
ebay (i.e.,stamps in albums) fall into two broad categories. There are sales by knowledgeable dealers, usually in auctions or "best offer" scenarios, where the dealers don't (and as a practical matter, can't) make representations about the conditions of all of the stamps, and they are very realistic about the 'fair market value' of the collection. (The fmv of a collection is generally far, far less than the catalogue value of each stamp.) Buyers can get a good bargain, but there are usually no assurances regarding the condition of the stamps. The other category of sales are typically from individuals who don't have a clue what the value of there collection is worth - they see a few "older" stamps (and anything printed in a single color counts as "old") and they think it is worth a fortune. I expect that those collections never sell.
Good luck finding a home for your collection!