How to collect rent? Mail to home or P.O. Box？

Hi everyone, I am moving to a new house soon and am going to try to rent my current house. I got 2 questions here and hope you guys can give some advice?

(1) Should I get a P.O.Box for receiving checks from tenent or just let the tenent to send the checks to my new home address? Some people told me that I should have a P.O.Box for that. But it's also extra cost.

(2) Supposed the rent is due on the first day of the month. Is that the day that I should receive the check or the day that the tenent mails the check out?

先谢了！