Your earned income is approximately $155k. You own a primary residence worth $460k, with only $20k in equity. The loan on your primary is almost three times your income. You are losing money on a rental, and not all of the rental income would be counted in a mortgage application anyway, so the rental will not help you. You are also underwater on that property. You have $15k in cash, and all your other money is tied up in retirement accounts. Your net worth, not including retirement accounts, is close to zero. Your DTI is near the maximum permitted under most guidelines. You might qualify for a small HELOC, depending on the lender.
I think you need to meet with a couple of lenders that can explain to you very clearly what the rules are and how the numbers are calculated. Hearing the news from them will be more helpful than hearing it from this forum. Once you understand your situation, pick up a couple of real estate investing books that are focused on the numbers side of the business, not the glamour. I think Sword Guy mentioned Gallinelli's book in a recent post. That's a good place to start. If there is a decent real estate investors association in your area, attend a few meetings and chat up some of the more knowledgeable attendees.
Once you know what constitutes a good investment and how you are viewed by lenders, then you can make a reasoned decision about whether real estate investing is for you, and what sacrifices you would have to make to get started.