You asked about buying a car in full. What if the 4s shop doesn't give the invoice? The solution to this kind of shop not giving invoices is as follows:

If you refuse to issue an invoice when buying a car in full, this behavior will harm the rights and interests of consumers. Customers who buy a car can complain to the tax bureau and ask for an effective solution.

You can also sue 4S stores to protect your rights and interests from damage. When buying a car, you must ask whether the 4S shop can invoice the car after paying the full amount, so as to avoid the trouble caused by not invoicing high heels in the future.