What is the process for a mailbox?

[Yesenia Martinez]

I just recently closed on a duplex a week ago. I have not moved in yet, and currently have tenants living in the unit I will be living in. I won’t be moving into the Unit until April. The property doesn’t have mailboxes, instead it has 2 mail slots. Can I mount my own mailbox with my last name on it so that I can receive my mail separately? Do I have to go to the post office or what is the process? Or what can I do in the meantime to receive my mail until I move in?