[leggomylibro]

It's fairly common in newer and/or larger buildings; walk-ups and buildings with a single landlord don't usually do things that way. But a lot of people moving to big cities around here are probably familiar with the idea. They also handle maintenance requests, showing people units, and sometimes things like community events.

The USPS does also have package lockers - larger boxes with keys that get left in your mailbox - but they aren't universal and companies like Fedex and UPS rarely have access to them. You can also have things held at the post office.

It's not that there are no other ways of solving the problem, it's just that the lockers are convenient and requires very little planning or forethought.