Am I missing something about the math behind investing?

[Patrick Philip]

I was just reading a news story about a large real estate firm that bought a building for $154,000,000 and that the building has a NOI of $10,100,000. So cap rate of 6.6%.

I know that this firm most always buys with financing. Without knowing the details of their loan, I will take a somewhat educated guess of 80% financed ($123,200,000) at 4% over 30 years.

This amounts to loan payments of $7,058,107.68 per year. This will make their effective income = $3,041,892.32. 

Their 20% down payment would have been $30,800,000. This means that it will take over 10 years for them to see their initial investment back.

Is there something I'm missing?