We travelled to Yellowstone National Park as a family of 4 (with two very young children), as well as with the grandparents. We felt the property met most of our needs (it would have been nice to have had laundry facilities on-site; however, this was not a huge deal, as there is a laundromat in town). We stayed for nearly a week, so at some point, we did encounter a shortage in supplies (trash bags, toilet paper, paper towels), but we did find that once we contacted the owners, they were quick to respond to our emails and supplied us with what we needed the same day.
The basement property is located off of a gravel road. Initially, we were concerned, considering how the surrounding homes looked, but we were very pleased with the rental, once we stepped through the doors and found how clean it was (I felt the pictures accurately depicted what was there). There was another family with young children who stayed in the property above us and we were able to hear their little ones' footsteps scurrying around, but since we were travelling with little ones ourselves, we were willing to overlook the bit of noise we could hear through the floor.
The property is nicely furnished and well-maintained. And given that breakfast that is included in the price of the rental, through the owners' restaurant in town, Rosie's Bistro, you definitely get your money's worth from staying at the B&B. As others have noted, there are no restrictions as to what you can order from the breakfast menu and the owners extend a 10% discount towards purchases for lunch and dinner. That said, there were times when we encountered a huge rush at the restaurant (we were there in mid-June) and if we weren't lucky on timing, there was a bit of a wait until we were initially served (because of this, we noticed customers walk out from time to time). So to address this (and save us time, since it is a bit of a drive to see some sights in Yellowstone Park, e.g. it is a 2-hour drive one-way from Gardiner to the West Thumb Geyser Basin in the south... and that's not accounting for any possible bear jams or bison jams or any other animal jams you might get stuck in for potentially half an hour!), I took pictures of the breakfast menu and we wrote out our family's orders ahead of time, which we would hand to the server as soon as we got in and our food didn't take long to arrive. Having tried nearly everything on the menu, I personally recommend their white chocolate chip pancakes!