Here are some airports and nearby hotel recommendations. If you are thinking about getting an AirBNB or VRBO, look into Camano Island, Stanwood, Mount Vernon, Arlington or Lake Stevens. Those are good & close areas.
Flight
SEA
Seattle-Tacoma Airport is the main airport, other options would be Paine Field or Bellingham airports
Hotel
Angel Of The Winds Casino Resort
3438 Stoluckquamish Lane Arlington, WA 98223 (360) 474-9740
Hotel
Tulalip Casino
10200 Quil Ceda Boulevard Tulalip Bay, WA 98271 (360) 716-6000
Hotel
Camano Island Inn
1054 West Camano Drive Camano, WA 98282 (360) 387-0783
Hotel
La Quinta Inn & Suites by Wyndham Marysville
11430 38th Drive Northeast Marysville, WA 98271 (360) 659-1710