Yes, you can sell a house that is under construction. However, the process may involve certain complexities, such as transferring the ownership rights to the new buyer and ensuring that all dues are cleared with the developer. Additionally, the original buyer's agreement with the developer will dictate the terms under which the property can be transferred, and in some cases, the developer may charge a transfer fee. It's important to communicate with the developer and possibly seek legal advice to ensure a smooth transfer process.