You can't apply for a 30% discount rate at present.
The interest rate of commercial loans is set by the state, and the discount is determined by major banks according to their own lending situation and market conditions.
At present, the interest rate concessions implemented by most banks are 15%, and a few banks can relax to 20% for customers with better qualifications.
The 30% interest rate you mentioned has not appeared for nearly 10 years, and the last time it appeared was in 2008. Due to the low transaction volume in the real estate market caused by the financial crisis, the 30% interest rate is also a way to stimulate transactions.
Now that the real estate market is rising and transactions are active, a 30% discount will basically not appear!