In what ways could this situation fail?

I want to find out if it’s realistic to be able to sell our home and buy a new home outright with the profits. I would not be taking out a mortgage for the new house.

The situation is, our current home is too big, too expensive, and not in an area we love. So I got to thinking, we could currently sell our house for twice what we owe on our mortgage, take the profit in cash, and buy a new home outright. No mortgage payments on our new house equals no more problems.

Now, tell me how this might not work out? Would the timing not line up? Would we be homeless at some point in the process? What scenarios could we face?

*And no, taking out a mortgage on the new place and paying it off once we get the cash isn’t an option as we don’t have the credit for it.