When you manage a apartment building, the rules should be the same for all tenants.This kind of favoritism causes problems, and can cause tenants to act out against each other.This is also what happens in schools when a teacher plays the same game.Then they wonder why students get into fights in school.As a manager in whatever kind of job, you should know how to be fair,not to pick and choose according to who you like or dislike.This kind of behavior needs to stop.If you can't manage fairly, then it's time to quit and let a fair minded person do the job properly.