The reason for the transfer and loss of property is not the owner. How to understand this sentence

The property is an indoor house of small business owners. If you sell your house, you must go to the real estate trading center to handle the transfer of property rights, and you will no longer be the owner. Due to the renovation, storey addition, fire, earthquake, explosion and other reasons, the original house has been changed, seriously damaged and collapsed, which is called loss. You also need to go to the real estate trading center to go through the formalities of house change and cancellation.