Mail delivery issue in turning a SFH into a duplex

[Nate Ferrari]

Hey guys! I'm interested in turning some SFHs into duplexes by finding a property that would be conducive to that. I asked my realtor about it and he quickly said he would not recommend it because of the issues of the postal service only having one mailbox there and that it could potentially be illegal to deliver multiple families' mail to one box. Has anyone else successfully navigated the mail issue so that USPS approved having a second mailbox? Just want to be sure I keep it kosher and don't commit some kind of federal crime. Thanks!