I precisely explained this to the brokers I spoke with, yet they are suggesting that the loan will show up on my credit either way.

How come in the final analysis with the rental calculator, the chart shows that in year 30 the profit when sold is way higher than the actual value of the property?

At the very least you will know you will not build equity, but it's very calculated risk.Second issue with higher interest rate, the overall appreciation chart is also declining, if the past US residential grows by 15%-30% IRR depending on the area.

No one can precisely predict the very bottom of the market so as long as my numbers work out positively, I should be able to withstand the market turbulence if it should come.

You can tell this by looking at the charts

First, let me congratulate you about getting your hands dirty, Not everybody is courageous enough to take action.I understand your reluctance to put real estate under contract if you don't know your numbers. 4 units is still considered as residential and you should be good to go with residential numbers (although I would be very precise in this case).

I am a 25 year old living in South Florida (Broward County to be precise), and will be getting ready to purchase my first home in the next 6 months to 14 months.

LADBS publishes a chart with the answer to your question.

Please provide more details on the originator and more precisely where you bought them. 

Kyle,Your ambition is commendable--just make sure you give the proper time and attention to learning whatever your military trade is going to be; these are formative years for your military career and you don't want to neglect your training (I was in flight school at your age and there's no way I could have thought about real estate investing).That said, you need to decide your specific real estate ambitions and then chart out how you want to get there.