Typically I change my price after two weeks of vacancy.

A duplex should have a lower cost foundation and typically has less windows and exterior.

We made the mistake of thinking the person who charged less was the better option, however in the long run we spent more.

I've considered different options, such as refinancing this home to make the land a separate transaction or even selling my house to build a duplex, (since I am not sure if I will be able to get financing for the construction project if the land and this current home are on the same loan).

Try to narrow down your options to the top 3-4.

Rent assumptions are typically an input, not an output.Similarly, a calculator cannot tell you where to buy. 

I have no dog in this fight, but the abundance of 2-4 unit options in good parts of the city provide a better long term opportunity.

Typically, getting into the 5-unit range can get overwhelming for people and take up too much of their time.I use QuickBooks Online for all of my clients.

My message is more about offering a few options as I am a licensed broker + real estate investor.

I have heard of some evictions taking as long as 6 months when the typical time to evict in Indiana is about 35 days.