Is it illegal for the company to make a down payment?

This is illegal.

For your question "Is it illegal for developers to buy a house in advance?" Please reply as follows: It is illegal for developers to buy a house in advance. According to the Notice on Regulating Housing Financing and Strengthening Anti-money Laundering jointly issued by the Ministry of Housing and Urban-Rural Development, the People's Bank of China and the China Banking Regulatory Commission, it is strictly prohibited for real estate development enterprises and real estate intermediaries to provide down payment financing for house purchases in violation of regulations. Real estate development enterprises and real estate intermediaries shall not advance the down payment for the buyers or advance the down payment in disguised form by stages, shall not provide down payment financing for the buyers through any platform or institution, shall not induce the buyers to pay down payment through financing from other institutions in any form, and shall not organize "crowdfunding" to purchase houses. The phenomenon of down payment by developers is likely to lead to chaos in the property market and lead to systemic financial risks, and the regulatory authorities should strengthen supervision in this regard.