I tried this once, spent $50 on a big pack of $100 business cards that I put a QR code in that led to my website. Got zero responses. It’s a fun idea, but at the end of the day the fake $100’s don’t always get into the hands of the people that you want them in so it ends up being a waste.
I remember those sites from over 10 years ago. The idea was to get homeowners to hold on to the cards for wow factors and show the cards to their friends. No card is going to attract a seller that isn’t motivated. A motivated seller will call a number on a napkin.