Planning on a once in a life time road trip for 4 weeks next summer, starting in Seattle then Bellingham. Maybe go to Vancouver Island, Squamish, Whistler, but want some natural trail riding as well as park and we want to take our own bikes. Should we hire a campervan or car? any advise or links to good Accomodation, guides, uplift service and vehicle hire would be much appreciated.

you need to go further north from whistler – Up To the Chilcotins

https://www.trailforks.com/route/warner-lake-float-plane-drop/

here an old trip report from 2008 when we went there

http://www.mtb-hol.com/Canada2008/Canada_2008_MTB.html

I haven’t done that kind of trip up there, but it’d be excellent.
For transport, I’d definitely recommend a car over a campervan. The difference in cost is pretty big, but also the ability to drive around easily, not worry about length or height etc will be useful. And bear in mind that ‘car’ also includes full size SUVs, which have space to fit 2 bikes with wheels on, 2 people and all the gear you’d need, with space to spare.
You should be OK for renting in the US and driving to Canada (or vice versa), but you’ll have to return the car to the country you rented it from.

Depending when you’re thinking of going, definitely plan some of your accommodation ahead for the busier places.

I’ve just booked to go to Vancouver this Summer with the family and drive down to Portland to stay with friends. Nothing more to add at this point but I’ll update with our experience. We are also visiting Whistler and various other riding spots around the Pacific NW.

There is some great trail riding around Oakridge, speak to theguys at Willamette Mountain Merchantile. Bend has miles of trails too. Don at Sunnyside Sports should be able to help you.

If hot springs are your thing. Check out the Idaho Hot Springs mountain bike loop. We stuck to the gravel roads, there are some remote single track trails that are tagged on

http://www.crazyguyonabike.com/doc/MCandBoblogoHotSpringingaroundIdaho

Hi
I have, give me a DM and ill give you some of my findings.

Did a month in Oregon a few years back. Would echo the comment to take a car rather than a camper van. Otherwise, the riding may be too far away but for @Dark Side, Mackenzie River Trail and Oakland (I think it’s called) are worth a trip.