The time it takes to sell your current home is unpredictable. There is no crystal ball that exists that can tell you exactly how many days it will take. Selling your current home before buying a new home will put you in an ideal position to negotiate on the new home you’re purchasing due to the fact you are purchasing without the sale contingency of your current home.
One risk of selling your current home without buying a new home first is the chance of not being able to have a place to live. There are options if your current home sellers before buying another though. A “rent-back” can sometimes be negotiated with the buyer of your current home. A “rent-back” would allow you to retain possession of your current home for a certain number of days after closing at the expense of paying the buyers mortgage. A “rent-back” allows for additional time to find a new home.