We did something similar this past summer. Glacier is beautiful but be ready for BIG crowds. People not inline by about 4am were turned away. Will probably be better in the summer when you go. Flathead is nice for fishing and scenery but should not be on a 7 day itinerary. Jackson is gorgeous (you MUST see Tetons) but very expensive. Good luck!

At Polson, on the south end of Flathead Lake, there are at least two public swim beaches. Polson bay near the Kwatuknuk Lodge and at the park west of downtown.

You can stay in Bigfork or areas surrounding Flathead Lake and look for a bed and breakfast or renting a cabin etc. You will need to Google and fine tune the options available.

And I am in the Mountains quite a bit, and yes we see bear scat etc....but just be loud and in groups and they'll get out of your path. I am more Leary of all the MTN Lions than I am of bears or wolves in the Flathead area. And again....in the mountain terrain for the most part. Down along the shore enjoying the lake you have very little to worry about animal wise.

VRBO might be one to try.

We found a beautiful place on homeaway. we stayed at a magnificent home in Finley point. It was a trip with two couples so our needs are different than yours. A few musts: Joe Arnold at Flathead Lake cheese is awesome. Small place making solar powered cheese. Great cheese. Tell him Rocky sent you. Glacier National Park...take the going to the sun road...fabulous life changing views. Lake Macdonald in Glacier is beautiful with cool rocks on the lake bed. Big Fork is cool quaint shopping place. There are quite a few places to rent boats or kayaks to enjoy the lake. Hope this helped

The photos were taken at a lakeside park in Lakeside, Montana. The park is new to me, but Flathead Lake is just as beautiful as it was when I lived at Kalispell Air Force Station over forty years ago.