I think the biggest thing to make me feel at home in a place, is the amount of freedom that I have. I have stayed with friends and relatives, and the feeling of being restricted really affects me. The second big one is the level of comfort. If there are things to fix after moving, or if things like the pillow or bed don't feel comfortable, then that doesn't make me feel at home.
Having a place to one's own, or oneself and partner, certainly brings freedom and that can give a person a nice feeling. I have that myself, it's why I'm so selective with who comes here, and it's one of the things I like. I also don't like neighbours to be too close.