Just an idea I had. You know how petco had/has that build-a-betta thing? Well, what if you were put in charge of something similar? What would you include with a betta fish? Keep in mind, most buyers want something small-- most people don't have the space for 10-20 gallon tanks-- while smaller tanks that can be fitted on desks, counters, dressers, coffee tables, ect, are more buyer friendly.
So just for fun, make a lift. Tank, accessories for the tank, some sort of food, and perhaps your own care sheet, ect. Also, just for kicks, try to include a price range for the bundle, and maybe even some pictures. Bonus points for people who can stick to one store (ie, all petco/all petsmart/all walmart). Not only do I think that this will be sort of a fun activity, but we can maybe create a sort of list for people to go out and look for, as well as general ideas of price ranges if you can collect those too.