I'm running your numbers and getting in the low 20% range.

I'm currently renting and when  decided I wanted to focus on real estate investing, I decided not to buy in Tampa because of the low MF inventory and in home house hacking is not for me.

Rates are high, usually in the high 8s or low 9s, and you may pay 2-4 points on the loan. 

I applaud you for putting it out there but 1) maintenance/cap ex is far too low for a duplex 2) no PM. 3) vacancy at 1% will be challenging if achieving near market rent.

Prices a few years ago were based on expectations of (in addition to interest rates staying low): - Then current operating cost assumptions (like insurance cost expectations being flat)- A seeming disregard for record levels of new inventory / supply hitting the market- Extremely high inbound migration expectations which are likely to not be met, due to both natural disasters and the boomerang effect when people from California or the Northeast move to the American South and hate every minute of the humidity, the large and relentless swarm of insects, and the occasional hurricane. 

Assuming a 40% expense ratio, the net operating income at the current income level would be around $19,440 annually and $28,800 after renovations.At a $360,000 asking price, the cap rate based on current NOI would be 5.4%, which is low for a park with park-owned homes and required renovations.

From choosing a property management company to landscaping companies.  

Low value markets might be Pennies on the dollar like you allude to. 

You’re in a great position with a property that’s appreciated significantly, a low-interest mortgage, and clear goals to boost cash flow and transition into full-time investing.

@Bonnie Low I was not including debt as I want to know how a cash buyer would look at the deal.