Hey Carlos - I'm on the other side of DFW from you. Along the lines of what Shawn was saying, could you get another property for $30k? If so, perhaps a HELOC for the $30k and then use the FCF from both of your investment properties to pay off the HELOC. Once you've done that, lather, rinse, repeat. That way, you're not highly leveraged.
According to Bankrate, you could potentially get a 4% HELOC if your credit is good. That would be a $303.74 payment for a 10 year term. Your net profit from the rentals, using the 50% rule, would be $650/month. If you could throw that at the HELOC, you'd have it paid off in 4 years, 3 months. If you could throw an extra $650 a month from your other sources of income, you could pay it off in 2 years.
Even if something doesn't work out, as long as you're comfortable with that HELOC payment, it seems like this approach would be a low-risk way to use a little leverage to build your portfolio. As the portfolio grows, it should take less and less time to pay off a HELOC. Once you get to the point where the portfolio throws off enough FCF to pay off a house in a year, don't use the HELOC. Instead, save up the money from the properties to buy another one with case. That's what we do, and while you want to be doing deals all the time, the reality is that if you can get to the point where you're buying a rental property with the numbers like you're getting once a year, you're going to be in a great position!