Pablo - dont be scared of tennants not paying rent, yes it needs to be factored in but the return vs risk is positive.
Breaking even on a rental is no problem at all, I have a property where I am paying £46 per month out of my own pocket - but guess what? since I had the property (approx 2 years) the increase in property price as far out weighed the £46 per month!
Yes tennants are a PITA, yes it takes up some of your time, yes sometimes they dont pay - money is seldom earned without some kind of outlay from yourself. In 5+ years of tennanted properties (touchwood) I havent ever had to take anyone to court, make sure your tennants are proffesionals, meet them personally, get an agent who does correct searches and some even guarentee rent nowadays.
With the finances you have explained here it seems pretty easy to get a BTL in your situation, and it will put you in much more of a powerful buying position for your next property also (i.e. nothing to sell)