Lake Pleasant in Bothell is very nice, if you can get a spot, and not too bad of a drive to Lynnwood.
At all costs, avoid anything off Highway 99. I've driven through them all. You just don't want to go there. I think there are 3 or 4 total.
If you are willing to drive a bit further, there's Emerald Springs RV Park in Arlington. It's new and has full-timers but all in new rigs. Not much for facilities, but they have bathrooms and full hookups.
https://emeraldspringsrv.com/
In a pinch you can also stay at the Evergreen State Fairgrounds in Monroe. They have 50amp and water, but no sewage. It's cheap though, only $25/day and generally pretty empty (which isn't all bad.) We stay there occasionally to satisfy the 'gone once a month' requirement at our camping club nearby.
Hope that helps.
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2018 3950BR - MORryde X-Factor, Disc Brakes, 3rd AC, Stacked W/D, Winegard Trav'ler (DTV), 2000w inverter, EMS-HW50C
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