Maps are a great temporary solution that could be easily and fast implemented. But if we want to make the whole thing much more integrated, informative, and updated in real-time, I would suggest a different system.
Locating product via product stands with wifi signal receivers or location devices
Imagine entering a shop and looking for a few products. You previously marked the items, which have their position registered in the system. The application receives information about the stands where the products are and know the location inside the store. The application opens an interactive map once you entered a shop and points out the location of the items.
This way shop owners can change the arrangement of the stands inside the store without worrying if the customers will be able to find everything.
No need for hiring a person or a company to update maps.
Additional benefits and opportunities