I am working on coming up with some sort of side hustle or some means to make more money, pay down debt, and start setting aside money for investing.My thought for the career change is hopefully a pay increase, but also a way to gain first hand knowledge while earning income and building my portfolio.My questions are this:1) Would making a career change to RE be advisable?

You may want to engage an accountant to look over the returns to see if you potentially missed some expenses that can lower your tax liability, thus reducing your monthly payments to the IRS.

She won't cash flow, but she will likely only be paying a fraction of what she would be otherwise paying for rent or to buy her own place.I also wouldn't say she has to forgo these things for the next 10-15 years, just long enough to build some equity and save up a little more money (which she'll do given the reduced housing costs that come with house-hacking).I think your main constraint is the HNI loan.

The best interest rates and down payment amounts are on owner occupied houses.   30 year mortgages are fixed for 30 years and help with increasing cash flow, while 15 year reduce cash flow but pay down the properties quickly.

I just graduated college and am focused on reducing debt and improving our financial situation.

Having an attorney go over the operating agreement helps with both ensuring that it covers your specific situation and will also give you a mediator - saves a lot of drama and helps in forming a fair document that reduces conflict.

You earned it!

I will live in one unit while renting out the other units to generate a positive cash flow in addition to my earnings from my full-time job. 

I’ve reduced the price greatly and offer seller financing for anyone looking to invest in the property at a discount.

@Anna FelkaTo echo the other already great answers, learning as much as you can will reduce that feeling of uncertainty you're feeling.