Friend of mine if flying in from idaho. He's bringing his handgun with him in a locked case as per what airlines requires. Far as I know theres no restrictions on his having it here other than abiding by standard rules of how he transports it as a CCWer vs non CCWer. Right?

Washington has reciprocity with Idaho for CPL's, but per the ATG website, we only recognize Idaho's "Enhanced permits", whatever that means.

No law prevents you from transporting a firearm from out of state into Washington.
The more the merrier.

Yep! Bring them in. Rifles too!

I always make a copy of the airlines policy for transporting firearms.  More than once it saved me having this with me.  Case in point flying out of Seattle the baggage claim lady told me they could not transport a handgun.  I informed her that yes I can transport a handgun and then proceeded to give her the copy of the airlines policy for firearm transportation.  She said that she needed to go check this out.  About 10 minutes later she came back and said that I could indeed transport my handgun.  Not all of the folks behind the counter are informed about firearms transportation and have no idea what the airlines policy is.  Other times I get people who do know the airline policy and it goes smoothly.  You should also get to the airport to allow enough time to deal with the people who aren't informed about transporting firearms.  MC

I drop my bags off with the TSA directly at SEATAC. I see the gate agent first, ask for two firearms declarations, sign them, get the bags weighed and tagged, drop a declaration in each bag and lock each bag.

when the fuck do they even get to ask this? I haven't had a firearm inspected since the mid 90s, and I think that's because the gate agent wanted to see WHAT'S IN THE BOX

I think the problem is you're showing up in baggage claim trying to check a bag.

Vegas is nice, they withhold all declared luggage for pickup at one point. In Seattle, sometimes it lands on the belt, sometimes behind the counter, sometimes in oversize items. Same case.

just remember to check your bags.