You can, but Coast also does walk-ins so you can do either

I would not go formal there. Business casual or hip-nice would be fitting.

No, it's two ways.

No.

They're not required but depending on the time and day it could be a good idea

I don't think they will turn you away, but it's a nice place. Pants world be good

Casual, but being a bit more of an upscale restaurant you will see lots of people in business attire.

It’s definitely not inexpensive but not so expensive as well