Don't use any private company, only use travel.state.gov. Make an appointment, fill out the DS-82 form, have your photo taken in the cafe in the lobby of the building that the Seattle Passport Agency is in, present your old passport and the fees (I think it's $170 for the renewal fee and the expedite fee). And be very kind to the staff.
What jeff said. Any private company is most likely a scam. you will also need proof of immediate travel to get it same day. That could be airline tickets or a hotel reservation. It believe the cutoff for same day is 10:00 am. Good luck!!
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