Support with Due Diligence needed

[Dhanush Kondoth]

Hello Ladies and Gentlemen,

I am looking to buy a property in Indiana. This is a 12 unit property which is 1 unit short of 100% occupied. The property manager is one of the tenant and works in return for free rent. He has been there taking care of the property for 11 years. The current owner bought the property from estate sales after the original owner passed away early this year. He may be willing to do seller financing provided I can come up with a decent down payment that is agreeable to both of us. 

I have SFR and Duplex in Columbus but never owned a apartment/commercial property. What are the Due diligence I will need to do additional to what we usually do for residential properties?

Any other questions or red flags I need to look into? 

So far this is what I have done.

1. Checked the county website for facts on the property
2. Talked to the owner to cross verify what is on the county website. 
3. Took a virtual drive around the area via google earth/maps
4. Looked at demographics, market rates, market analysis, crime report and future prospects

 Its not Indianapolis but its a small city. 

Any thoughts and supports will be helpful. 

Thanks

Dhanush