The sponsors I work with have provided double digit annual returns to their investors- better than most of us can get on our own in a long term hold.  

Even if the present owner started it, if you were to buy it, you'd likely have to start all over.

The numbers you are presenting for the Duplex seem a little too rosy.  

A lot of the options mentioned above are great tools to use but definitely consider an option that presents a one-stop-shop for collecting rent as well (and has faster payment processing).

Based on a double eviction I would expect the present owner was a terrible landlord, completely burned out, and the units are most likely in rough shape.

I'm putting together a group of investors specifically for tax deed purchases, and I was hoping I could present a reliable alternative to quieting title where we could control for cost and time frame.

Make sure you know the value in it's present condition - have a price in mind that you want to pay.You have 2 options - 1.offer to buy it, financing it - give the sell their price and money - rent it.

I've been presented an opportunity to provide a $40k loan on a $45k land purchase.

So to sum up, I've got goldmines of information sitting in a box waiting for me to dig it up. 

They could, of course, turn on the bathroom fan (if present) if the odor is confined to the bathroom when they are in there.And it's not going to be resolved.