I own a small store and implemented QR payments last year. At first, I thought it would be complicated, but it turned out to be easier than a POS terminal. After searching for a long time, I finally found a decent solution from A-Pay. You can
check this website to get a better understanding of how it works. They supports the Bangla QR standard, which works with most local wallets using a single code. You just put up one QR code at the register, and customers can pay with wallet. As for security, Bangla QR codes are dynamically generated and virtually impossible to forge, unlike static codes. Have you tried any cashless payment options at your business yet, or are you still considering it?