Newbie question about leveraging

[Eric Bates]

Sorry A newbie question is it better to have a rental property paid off making $800 after taxes and insurance or to borrow against that house to buy another house so after mortgage payment you would make let's say $300 a month and the new property you make $500 after everything is paid so now you are back to the $800 a month I don't understand the benefit of leveraging the first house to make the same amount of money sorry if this is a dumb question I was reading an article saying you should leverage rental properties