You can fly into Medford for Ashland but it’s almost as bad as flying into my town (Eugene) lol. Expensive and weird schedules. Second-tier airport cities— ugh! I told my husband once we retire I vow only to live in a hub city 
@walkinghome - then you will really like the temps during the day. If you’re outside in the evening, you will need sweatshirts and/or long pants. When the sun goes down, it cools off quickly. It’s common along the beach to see people making campfires and sitting out by them after dark, making s’mores, etc. But I remember almost everyone in sweatshirts and/or long pants if they’re outside for any length of time in the evening… more than just walking from town to your accommodation. It’s very windy along the beach, so perhaps if you stayed at the retreat place linked above, which is a couple of minutes from the beach (I’m assuming via car), then perhaps you’d be a bit protected from the wind. Regarding the wind at Cannon Beach… there’s a reason there are so many places to buy kites in town! You will see them everywhere!
I’m starting to come around on the cooler temps and really like the Oregon Coast. We’re still struggling to find housing for all. Many houses seem to place an emphasis on over the top master bedrooms at the expense of more bedrooms, or they have bedrooms with two queens (our adult children do NOT want to sleep with us, and vice-versa). Or they have a bunk room, and again, adult singles are not keen on that either. We do however want a large well stocked kitchen and the houses that seem more dorm like often have old timey kitchens. We’ve found that a minimum of two refrigerators is important. I liked this house that two of you linked: http://www.vrbo.com/201536 but that means driving to wherever we put the rest of the people. I know that sounds silly, but we’ve been spoiled by having houses close enough to walk or bike to. That might be the solution though if most people stay there and then we get one or two smaller houses on the beach.
Those houses in Cannon Beach look fabulous. I looked closely at the listing because they are of interest to me, too, and they seem like they’d be too small for your group, even with supplemental houses. The main house is essentially a large four-bedroom house, with the additional “kids zone” set up with an additional 4 single beds. The guest house looks like a nice-sized two bedroom guest house. Their “sleeps 28” claim seems to be a stretch, by a long-shot. But it looks like a fabulous place for a group of 12 adults and four or five kids!
Just know that Cannon Beach is crowded during the summer. Fun, but crowded, which is why we end up in Westport or similar.
"It was me who mentioned Leavenworth. Yes, the town itself is all done up like a German town. The city leaders did this years ago to purposely become a tourist town to save it after logging died down. "
And it was a very successful move! According to our Bavarian-born exchange student, the town does have a very authentic Bavarian feel. She even liked the Getman food served at Andreas Keller! Lots of hiking and river rafting, too. The city of Wenatchee is just a short drive from there, and there is some wine tasting for the interested. 
@walkinghome - I would call the people who run the Seascape Retreat House, and ask them for their recommendations to accommodate your needs. They may have another property within walking distance - I don’t know that for sure, but I do know they have other properties, so it would be worth checking.
Welll, after all that effort, we’re going to Lake Tahoe! Huge house with room for at least 24 in beds! I don’t want to post the actual house here, but just go to VRBO and look for houses with 6+ beds and you’ll see all the choices we had. In the end, it pretty much came down to the house…
Lake Tahoe is nice too.
You can watch The Deep End!
Very atmospheric.
http://www.rogerebert.com/reviews/the-deep-end-2001
So jealous… have not been to Lake Tahoe yet! I’m sure it will be great.
Lake Tahoe is fun. I’ve only been in winter, but it’s on our summer bucket list also. There is some great hiking and biking to be done, and of course the lake itself. Enjoy.
Sounds like a great choice! I’m glad you found a house that’s suitable.
Wonderful choice!!!
That’s a large enough playground for your big group! Enjoy.