This is what we call the original House Hack. Because you are living in the unit, you receive owner-occupant mortgage rates rather than investor rates. This can save you thousands up-front and ongoing. In fact, smaller down payments (even 0%-3.5%) are also available with VA or FHA loans.
With a fixed-rate mortgage, your principal and interest payments stay the same, but the amount you receive for rent can increase over time – even 5-10% per year during times of extreme housing inventory shortages.