I would think duplex property might result in lower rent than a detached single family property.

I feel like the risk/ reward is best in the lower middle, stereotypical "blue collar" tenant in my market. 

I agree with @Irfan Raza about having lower down payments being more beneficial. 

Looking for advice on how i could lower my mortgage near $500 over the next 4 years

That will keep your P&I payment much lower than the 15 year you have in your report.

Air might have lower fees to the end user but I just don't get many bookings from them unfortunately.

My wife and I are looking to buy our first home and want to make use of the house-hacking method to lower our expenses and start to build real wealth.

Homes in nicer neighborhoods that produce consistent (albeit lower) cashflow, appreciate and are able to be left as a legacy will be in different neighborhoods and/or markets.I'll finish with a comment on turnkey providers. 

If there's an appraisal it might very well come back lower than 125k and kill the deal. 

It does not make sense to lower your rent because he was living alone (assuming they have not been living there from the beginning without your knowledge) so I do not understand your logic from the beginning.