Hi Guys,
Primary issues would be tenant quality and vacancy.
Point is, if an SFH is $50K and a Duplex is $50K, the SFH rents for $800 and the Duplex rents for $550 / side, naturally you want to favor the Duplex because the returns are higher. I'm assuming that this is the reason you want to invest in a Duplex? If not, I'd be interested to hear what your rationale is.
As a fellow out-of-state investor investing in Indy, I wouldn't recommend chasing paper returns, especially on your first investment. I would suggest hiring a broker and soliciting input from a Property Manager to determine if the property you've identified is in a good area and fits into your investment criteria.
I previously sent my Property Manager examples of two duplexes I thought had good numbers, he said they would not even be willing to manage those properties due to the area they were in.
That is not to say that good Duplexes aren't out there, they are. This is verbatim from my Property Manager "On paper, you may see higher cap rates, but the vacancy and associated costs with lower value doubles are up there. If you buy a double, get it in the right area. The right house in the right area does not come up often."
There are a lot of challenges with out-of-state investing, and I would encourage that you really take your time and perform the right research for your first one, Lord knows I made a ton of mistakes on my first one. You want to leave with a good taste in your mouth so you feel confident when you buy your 2nd, 5th, 10th, etc.
I hope that helps.