Yes, the certified accountant's term is fully-amortized. Each fixed payment includes an increasing share of principal and a decreasing share of interest. This applies whether the interest rate is fixed or not.
Also you always own the home as long as you are meeting the terms of the mortgage contract.
There are quite a few mortgages in the states that don't pay the principal until the end, but it creates drama at the end. Some friends of mine went that route and when the principal came due after 5 years, lots of assumptions turned out to be wrong and they had to sell to pay back the principal.
Also you always own the home as long as you are meeting the terms of the mortgage contract.