GTA Online Diamond Casino and Resort (DC&R) does not allow you to have more than six houses or apartments. Nor does it allow you to sell them. It only allows you to exchange them when your number of properties has reached the limit of six. If you don't have six houses or apartments yet, you must buy them before you can sell them.
Steps to buy Apartment or house in GTA Online DC&R:
- Open your mobile phone
- Select internet
- Go to the Money and Services menu
- Select the Dynasty 8 Real Estate website
- Buy property
Steps to Sell your Apartment or house in GTA Online DC&R:
If you already have six different properties in the game, you can start exchanging them. Repeat the same sequence above, trying to buy the seventh property. The game will warn you that you cannot have more than six. As a result, it will offer you to change one of the apartments or houses that you previously bought for a new one.
Select the property you wish to sell in the exchange menu, which will appear after the Confirm Exchange operation alert. As a result, the game will return the money to your property account for which you decided to exchange.