Claudia's place is fantastic. The view is epic, of course, but the loft space itself is so beautiful. Claudia greeted us when we arrived and since my boyfriend and I both speak a small amount of Spanish and French, communication was fairly easy with the addition of Google translate. She gave us restaurant recommendations and got train passes for us since we didn't want to drive back into town for dinner. There are 2 train stops very close to the house. We loved watching the sunset and sunrise from the peaceful balcony.
Some things to note-
The drive up the mountain can be a bit scary in fog and at night if you have a large vehicle or aren't used to skinny roads with hairpin turns. Some of the streets in the town on the way up can be quite tight and there's currently some construction on the route to the house with no clear detour, so you might want to download your map ahead of time for navigation.
There are lots of steps up to the house and loft and we were advised not to roll our suitcases on the floor, so if you have a small suitcase or day bag you can bring I would recommend it.
Overall we would definitely stay here again. It's such a cozy little place and Claudia is so warm and welcoming. The town of Montreaux has a lot of cute places to explore, highly recommend!