Clearly, I need to do a lot more research and homework. This is a great thread. It shows both pros and cons of renting vs owning.
Don't forget that having a legal rental also involves some tax implications on your income, as well as looking into what you need to ensure it's up to code (fire ratings, exits, etc).
Everything is doable, crunch the numbers. Regardless, it takes work. Most people don't like that last bit.