You will be dealing with an older housing stock, so higher deferred maintenance and capex should be expected.

How much do you have to invest and what returns are you expecting to see?

I was surprised when the agent consulted the seller despite my offer being lower than expected, given the property's condition.

Once my zoning variance was granted, I expected getting the building permit would be straightforward.

To add to what @Jonathan Greene wrote:1) Understanding the local market, so you know what Neighborhood Class your building is located in, what Class your Building is (condition & amenities), and what corresponding class of tenants will be attracted.2) Using all this data to properly set your expectations and a realistic ROI.3) How to better screen prospective tenants, including catching fraud, so your property performs better.

If a person is 20 years old, and their life expectancy is another 60 years, then that $600/year adds up to a whopping $36,000,...total. 

This is in line with the expected seasonal trend and probably correlated to the rent increase in September.Rentals - Months of SupplyThe supply for our target rental property profile stands at about 1.4 months, slightly down year-over-year.

Your expected plan.  

Yes it can be worth it, just don't expect to get rich quick lolMidterm rental has been my strategy and I'll definitely be sticking to it for the next few years.

The challenge when renting directly to the government is that they expect below market rents.From what I've read in the past, most institutional investors look at these leases like US Treasury Bonds (extremely low risk) and expect a similar rate of return as bonds.Keep this in mind while you try to negotiate a rent increase.