i've been noodling on an idea about price transparency to lessen consumer information asymmetry, and this case might be a neat application: any ads should be accompanied by at least the highest all-inclusive price for the product in the expected viewership area. in this case, the mere inclusion of a price tips the viewer off that it's an ad.

this price would include all fees and taxes to get the exact item shown in the ad. in cases where the fees and taxes vary for the viewership, you show the highest possible price. you can show other price variations, but the highest must be the most prominent. not only would consumers get better information but markets would be more competitive and ads would be better targeted (so as to show the lowest price to each viewer).