Am I Doing This Right?

[Ryan Moore]

There is a property on Fannie's website in my area. List price of $39,900. Rents in the area comp out at $1000 median, so let's assume a low number of $900. Light fixer that doesn't look too bad, so figure $2K in paint and repair worst case. Assuming an offer of $35,000 is accepted, with repair, total price to be $37,000 and a Fannie down payment of 3%.

Monthly Rent: $900
Expenses: $450
NOI: $450
Debt service ($37,000 @ 7% for 30 years): $239
Income: $211/mo.

Even with rent at $700/month, doesn't this still produce a $100/mo? Am I missing something?