You should be working with a local Realtor who knows the area well and knows Glenview well.
Now most homes are listed for much longer than ever before.... it really depends on the construction of the home, (brick, all brick, full basement, finished basement) the updates and upgrades, ages of appliances, furnace, A/C roof etc. and then the surrounding neighborhood as far as price range of homes goes, and
closeness to train stations, highway access, shopping, parks, schools etc.
And then it depends on your personal needs as a family......
So moving from Seattle it would be highly recommendable to work with a local Realtor, it does not cost you anything as the buyer, and you will be well served with a good Buyers Agent, to explore other options, to get comparable properties that are competing with this one, and those similar that have recently sold --- and
the simple answer to your question is yes.....
An offer is just that, an offer to which the seller can counter, accept etc. and may be in this particular situation
starting at 10 or even 12 % below their asking price is reasonable, but hard to tell if one does not know the home, therefore an experienced, local Buyers Agent would be extremely helpful...
You may also want to consider surrounding suburbs like Wilmette, Northfield, and Northbrook......
Hope this helps!
Edith YourRealtor4Life! And North Shore Expert
Covering suburbs to the North of the city of Chicago from Evanston to Lake Forest
and Park Ridge / Glenview / Northbrook / Wilmette to Buffalo Grove and beyond
Edith always works in the very BEST interest of her clients!