As @Bruce Lynn highlighted, you'll want to take advantage of any time you have now to start taking your pre-licensing courses and exams so you can get started right after graduation.While you're doing that, I'd also recommend reading/listening to Hyper Local, Hyper Fast agent by Dan Lesniak.

One thing you might want to focus on now is getting pre-approved for financing if you haven’t yet—it can give you a stronger position when making offers.

We pre-screen all tenants and they must qualify. 

I have remodeled the unit completely prior to putting it to rent, including addressing pre-movein readiness checklist I was given by RL after they walked through the unit (small list of punch items like toilet paper holder, cleaning unit, door stopper etc.).

Old school ledgers and rent rolls written on notebook paper...

A short sale is basically a pre-foreclosed property, and the sellers Broker can walk them through obtaining a short sale approval with their financial investor/mortgage company… the seller is not liable for paying the broker or any additional debt that has been agreed upon by their investor/mortgage company, including the Broker’s commission.  

Quote from @Billy Smith: Having all or most of your rentals paid off is a great feeling with the cash flow rolling in .You know have a bigger shovel to buy more properties , folks get the fever want more more dam the debt full speed ahead .I read a lot saying what  is the rate of the  note ,you could deploy the money in  ,gold ,stocks etc....With just a couple rentals paid off in A -B area I put my kids though Division 1 state college.  

So, they are missing out of 200 dollars a month for at least 4 years (and maybe longer depending on where rates are when the PPP rolls off) so that is at least 9600 in opportunity cost by taking a slightly lower rate at the beginning. 

With this being my first apartment deal I am more unsure about underwriting this type of deal and was hoping to get somebody who is more experience in multifamily to look at the proforma, T12 profit and loss, and rent roll to tell me if I'm missing something or to let me know of things that I should be looking out for.

My only backup plan if I can't get verified funds is to assume the worst and to drop my counter offer even lower than my original due to the risk I would be taking on, and then when I do my in person inspection try and guess what rents are fair market for the empty units, and ask as many tenants as I can what they pay in rents monthly.Seller should give you all of his bank statements for the time he owned it, plus the operating financial documents (including rent rolls)that he received when he bought.Then find an apartment broker in the area and find out about rents in the building and in the immediate area.