@Sean Dulcio - I dove into duplexes right out of the gates putting 20% down and not living on one side but renting out both sides - I wanted until I was 25 though, you have time on your side by jumping in at 19. The one advantage I had was I felt like since I was 25 and had general business experience - I could "talk the talk" with my banker (who I had a excellent relationship with) and they took me 100% seriously. I'd suggest going the extra 10 miles on professionalism. When asked about specifics like debt coverage, I could fire off a number with 2 decimal places ("1.76"). At a recent meeting with a commercial lender, when asked about plan for leases I had a mockup wire bound booklet with me. My bankers response was along the lines of "We don't even see this level of organization and professionalism from our largest customers."
Good action steps, I'd suggest going to a community college and taking classes like Accounting (and just keep going, learn as much accounting as you can), Business Law and Finance classes. Know all the terms like Debt Coverage, Internal Rate of Return and all the future value and present value math so you don't just have the numbers but truly understand them.