While Octavio is probably correct, I do NOT have a WA license, but have two vehicles and a trailer registered in WA. They have never asked me for a WA ID or DL. You also have the option of getting temporary registration for the vehicle, up to 60 days (unlike Oregon) while you study and receive your Washington License, if necessary.
You have to do the driver license first then your car it's on the same place but not on the same side .plate to the right side of the entrance and driver license to the left. Have fun.
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