The Amazon building "Day 1" that house the Go store has convenient retail parking. The elevator exits you on the side with the Go store.
No parking lot. Parking anywhere in seattle can be a bit of a nightmare if you aren't a regular. I use ("Best Parking - Find Parking) app on android and it isn't flawless but it works. The amazon office is private work place as well.
There is street parking available in the neighborhood. Amazon office buildings surround the store but likely are private offices - you would need an employee invitation to visit inside.
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