This one being aimed primarily at keepers of small shops in maritime nations, although more lumpen categories may on occasion apply.
Most frustrating it is indeed to find oneself in a perfectly fine town and village and in need of a chemist or fruitmonger or cash-from-a-machine or toilet facility
and not to know where to find such a thing. Most frustrating too for the keepers of such shops or businesses or facilities, to be separated so sorely from ones willing participants.
And most buttress against back yards filled with nought but troughs of rust, or aged appliances without batteries.
So, the owner shall flood his back yard with salty seawater infested with fish, install a submerged windmill to create the effect of a nautical wake, and attract seagulls from near and far, who will circle about and screech aloft to advertise the business for miles around.
Seagulls shall be genetically engineered to exhibit a colour or glow relating to the business in hand. Chemist Seagulls might be green, Butcher Seagulls red, Baker Seagulls croissant-toned, Bank/ATM Seagulls silver and golden, and Toilet Seagulls a rich brown.
Attraction of the correct seagull breed to the correct business is achieved through the genetic engineering of the Magnet Fishes. So, Green Chemist Fishes are mint flavoured, Red Butcher Fishes are strawberry tinged, and so on. It's clear.
So, upon arriving in said town or village, our stranger glances aloft and picks a flock and walks and walks until beneath the flock, where they find the shop they desired in the first place.
In the case of multiple similar businesses, natural selection ensures the best man wins, as those seagulls flying highest would ensure the greatest return on investment and be able to fund more fish.
In the case of fishmongers, fish-making-skills speak for themselves.
This here also applies to Small to Medium-Sized Enterprises, such as accountancy firms, and also to fast food chains.
For land-locked nations, the scheme is also fine. Seagulls will only enter such nations on days when the weather is too ill at the continental coast. By definition, the weather is better inland. So on those all-important days, the advertising is free. Proprietors in land-locked customers are therefore advised to pay regular and generous subsidies to their alien colleagues at the coast.