Consider a used car market where sellers possess complete knowledge about their vehicle's condition, but buyers can only guess the quality of any given car. This often results in a situation where the prices buyers are willing to pay are too low to convince owners of high-quality cars to sell, potentially leaving only low-quality cars available. Propose one realistic mechanism or policy that could help solve this problem. Justify your proposal by explaining how it would improve the market outcome for both buyers and sellers of high-quality vehicles.