You can own only one house, but with the keyring you can rent as many as you like!
I'll give a key to my house for 500 currants for a real-world week.
It's a cottage in Bortola.
You can: use my trees (spice, wood, cherry), 8 of my 12 crops, my 4 piggies,
2 butterflies, and 2 chickens in any way that does not damage them.
You cannot: pick any item from the floor or cabinet, damage/kidnap/destroy any plant or animal.
As a guarantee, I ask for a 4000 currant deposit that I will return at the end of the week.
Enjoy!