Too many times I see folks counting on the appreciation of the home to help with their retirement goals. A big part of the problem with the real estate bubble of 2007-08 is that people used their homes like a piggy bank with HELOC loans they could not afford when real estate prices headed south.
When you retire you should aim to have your home paid for. No mortgage = peace of mind and less stress on the investment assets you do have. In extreme situations, like when someone has done a poor job of saving and investing for retirement, a reverse mortgage can help make ends meet, but it should not be a part of your plan.
Think of your home as a nice place to live!