Go to Properties/My Properties in the main menu, press the orange Edit button, to delete the property go to the options tab and click on the red button at the bottom right of “Delete this property”.
From the control panel, go to Properties/My Properties and click the orange "Edit" button. If the Rooms tab is disabled, go to Options to enable it. Once you've done this, you can access the Rooms tab and add as many rooms as you want using the orange +Add Room button.