Long story short - we have a house rented in Hungry Horse, MT but the other couple we are supposed to go with may have to back out. We are going to try and make a reservation in Glacier at Fish Creek campground as the backup plan. Has anyone stayed there and if so, any site recommendations?
I have never camped in my two trips to Glacier.. but since you mentioned house rental. Take a look at the rental cabins outside Glacier, available through the Forest Service website. Need something sizable on west side.. I can recommend Schnauss Creek. https://www.fs.usda.gov/recarea/flathead/recarea/?recid=66256 Very reasonable and we loved it.. just thought i'd mention.
We stayed at the St Mary KOA a few years ago. It was nice. Just a typical KOA. Iceberg Lake trail was awesome. Usually stay in parks, but I needed a place with hookups, as the next leg of that journey was dry camping.