1. How much will my monthly payment increase?
    
   
2. How much will it cost me to make this transition?
    
3. How much of a mortgage do I need to become qualified for?
    
4. What happens if I add in some extra money beyond the proceeds of my home sale?

So many questions -- all very helpful to think through, calculate and discuss.  The worksheet above can help you think through those numbers -- and it is available here as an editable Excel file.  Enjoy!