@George735
You need to get you lawyer involved to create a proper lease agreement between you and your proposed tenant, with a deposit which you hold.
I would never make a lease agreement for a year under Airbnb Terms & Conditions which are designed to protect Airbnb rather then you, as host.
Additionally, you'll have to provide all the utilities and benefits associated with your Airbnb listing and give Airbnb their circa 20% fee.
Do more research before you get involved in a yearly lease because most certainly you guest/tenant will have the upper hand otherwise.