You shouldn’t even know your tenant
Part of the process of finding a new tenant is checking references from previous landlords. I once called the manager of a small 16 unit aparment building to ask about someone who wanted to rent from me.
The manager simply said:
“I confirm that he has been renting here. But, I don’t even know him. The best tenants are the ones that you don’t know”.
The implication is that if a landlord knows a tenant very well, it likely means that there have been problems. You should strive to pick tenants who you will never get to know.