There was an item on the news recently about a guy building tiny mouse
villages in his back similar to some of these below google/bing images are worth a look through-I built a small hedgehog village from old tyres some years back.
https://www.google.com/search?sca_es...tive&ss ui=on
https://www.google.com/search?q=hedg...tive&s sui=on
oh and plenty of moss over stuff.
https://www.gardeningknowhow.com/orn...ss-gardens.htm