Has anyone invested in post offices?

[Mohit Asthana]

Hi, has anyone ever bought a post office before? 

A friend of mine introduced me to the idea and it's seems like something to look into. 

The USPS is a government entity that never wants to move and has a AAA credit rating. The rent may be a bit lower than market value, but the cash flow is going to be consistent. 

The leases could be either triple net or modified gross. Returns may be lower, but lower maintenance. 

This looks great on paper, but does anyone have experience actually buying them? They're as cheap as 100k and seems like a good introductory investment in a niche asset class.