I'm thinking about adding some value and exiting with a short term hold (3-5yrs) to trade up via 1031.

I'll trade dollars for that peace of mind any day.

If we're still ok, I'll try to buy it preauction if that's available.My experience with auction.com in the SW Ohio area is that about 15% of the houses listed wind up trading on their platform.  

I also use the old school method and drive around a look for “For Rent” signs and call the owners and see if they have any properties they are interested in selling.

I am a second year finance major and have been trading stocks since 11th grade.

They are all 4 unit properties or less, so they will not trade based off of a cap rate.The unit being vacant IS NOT A DOWNSIDE.

In parallel I've been learning about the general REI strategies out there.I have two rentals that i bought a few years ago but knowing what I know now, i prob wouldn't have bought them due to using traditional buying methods.  

I’ve been working for the USPS as a mail processing clerk for the past three years - I handle and organize letters and packages (via methods of machine sorting and hand sorting) for the carrier routes the next morning.Overall, the post office has treated me well, putting fairly decent checks in my pocket with some pretty sweet benefits to go along with them.

As far as other methods to lower your DTI, I've had success taking my insurance/taxes out of the escrow account to lower my monthly payments.

Definitely start first by getting educated about the various ways to get started, then consider all of the methods against your current resources (cash/credit/network/skill-set/income/assets/debt/time/knowledge/experience/etc...), desires, likes/dislikes, near-term, medium-term and long-term goals, and time that you have to devote to doing REI.