Is it easy for BMW to refund the deposit and make a complaint call?

It is useful to complain about the breach of contract of BMW stores.

According to the provisions of the Contract Law, the party who collects the deposit will double the deposit if it breaches the contract, and the party who pays the deposit will lose the deposit if it breaches the contract. So whether you can get the deposit back depends on who defaulted. If the 4S shop breaches the contract, you can complain to the Consumer Association, report to the Industrial and Commercial Bureau or get the deposit back through litigation.