On the note of OO, I do plan on living in the property I purchase for 1-3 years while I house hack, re-build up a solid savings, and renovate each unit.  

For some reason, nobody seems to think demolition and rebuild is a good idea here.  

From the "paint and carpet" cosmetic rehabs to a house we are finishing up now that was a 200yr old log cabin that required us to catch the top story of the home with industrial steel i-beams and remove the entire bottom half of the house and rebuild it from the footers up.

You moved to a great area and have a great set of skills in Web Dev, which you could utilize to gain relationships with investors building a new website, or rebuilding an existing website!

I'm assuming they are tearing down and rebuilding.

At $340k, it's not going to work and I wouldn't speculate about escalating rents or appreciation - not guaranteed, period...Nashville is very hot right now and the only way someone will make money on this duplex is if they tear it down and rebuild to flip.To give you another comparison, I just put in an offer for a 10 unit in Dickson for $300k - only 45 min's from Nashville.

I am currently trying to build/rebuild my credit.

I have discussed with my bank projects that would involve complete rebuild of houses, where the original house would cost more than 20% of the costs (likely around 50%), and they were fine as long as I could close the construction loan with my 20% in cash.  

I am hoping to buy a property to demo and rebuild into either an adult family home or rental. 

It involves tearing down and rebuilding completely, so its alot of work for my partner.