I'm currently working on our mortgage to increase our cash flow and make a sound investment. The safest bet is just to get a good mortgage broker to get the lowest interest possible in the market (they work for free in your end and get paid by the financial institution that will be working with your mortgage). My mortgage broker has secured 2.59% from current 4%. MB can explain you the savings you could have without changing the amortization. It could even be a combination of reducing your interest and increasing the amortization, maybe you only need to extend the amortization a few years to have the cash flow you need. The mortgage broker can do this exercise for you if you tell how much extra cash you need on hand. I have an excellent mortgage broker if you want the contact info. It is a very intelligent woman with great financial knowledge and very patient to explain all angles.