This can be improved and increased cash flow.

I am getting ROI of 12.88% at the moment. 1) Any advice on the ideas to improve ROI for the next home purchase?

I'm totally new to real estate and am hoping to meet and connect with like-minded people in my area.I'm an active duty military member, so if anyone has any experience with how I can use my status (VA Loan, BAH, etc) to improve my REI, please let me know!

@Deandre LeeI’m going to disagree about not adding square footage, you can still increase the value over and above the rehab dollars by just improving the building   I’ve bought many BRRRR projects and by just rehabbing kitchens, bathrooms, etc, I have increased the value above the rehab dollars, usually by 20-30K.  

The place has improved a little, because Dough, Thomas, and myself have controlling interest in that those communities... don't expect anything amazing, turnover is very high, and bank foreclosures are common at those price point, so much so, we don't even buy them for that price.

I created a calculator using excel and was wondering if there were any other metrics I should include or things that I did wrong or didn't account for or just any feedback in general to improve it.

That can be an opportunity, especially if you identify a way to improve something from C to B. 

You're improved expenses won't matter.What's your payback period on the $12k? 

@Jadi Akuti Ultimately that would be the decision of your employer but I would just try to sell them on why you would like to try it out and see if it helps improve your conversations with sellers.

As stated, I would look for other ways to improve curb appeal.