You can do most of this already, right? When you can choose from 10, 15, 20, 25, 30, 40, 50 year mortgages, take your equity, swap to a new house, pick the mort

You can do most of this already, right? When you can choose from 10, 15, 20, 25, 30, 40, 50 year mortgages, take your equity, swap to a new house, pick the mortgage closest to the term you want, and there you go. You will never get 3% mortgages to follow you through any refinance - if people like the ability to lower by refinancing, the cost is that if you refinance under a worse time you get higher rates. If you want the ability to lock in a 3% loan no matter what changes you make, you will have to pay a premium, so you would not get the 3% to begin with. But changing term lengths is pretty easy. https://www.mortgagecalculator.org/helpful-advice/how-many-years-mortgage-loan.php https://www.mortgagecalculator.org/helpful-advice/how-many-y...