I just received the financials and books, so I will definitely be taking a close look at those.

First, that investor telling you of a minimum IRR doesn't have a clue, IRR is rather irrelevant especially to predict, no one really knows what the IRR will be until the future.If you're going to look at the IRR, that 5K isn't your total investment, it's an additional 5K you put in to restructure your financing. 

(eg: If payment is not received by the 10th we the tenant will be processed for eviction"). 

Just make sure you screen tenants properly, and they will be a welcome addition to the neighborhood.  

Renovations are being completed within the next few weeks, at which time the property goes on the market.Scenario 1 - The property is sold, my note is paid back, and I receive 20% of the net profitScenario 2 - The property is re-financed, my note is paid back, and the property is rented.

But in addition, if the numbers look good, you need to get this house under contract.

Additionally, you could also choose to keep the house with the option of foreclosing on the property and take full possession.Does that help in any way?  

The most common general answer I've received is keep it simple while your small.

You have to also account for all the additional repairs and costs that would go into all the units to make it rent ready.

How many additional properties could you have bought if 75% of that money was yours instead of the banks?