Advice on mods on my Z? Moving to Renton/Seattle soon

[jooonnn]

Hey guys i plan to move to renton washington in the next few months. Im reading a lot of horror stories about mods as i have a 2013 nismo.

How strictly enforced is the exhaust law there still?

Do any of you guys have cold start complaints for neighbors?

It also notes how 2009+ cars do not need emissions tests as long as your car has a california approved stamp under the hood.

I know this is probably a dumb question as washington requires front plates. Do i have to register my cars in washington if i still have them registered to my parents house in south carolina?

Any other advice at all on anything and everything would be greatly appreciated!