Remember potatoes come from farms where there may be rats and mice, Check deliveries to make sure there is no sign of rodent activity, such as droppings, gnawed sacks etc.
Mice can get through very small gaps so make sure all external doors are close fitting. They often need a brush strip fitted to the bottom to prevent pest access. If outside doors to the preparation areas are left open they should have strip curtains or fly screens fitted, although ideally doors should be kept closed.
External areas should be kept free of vegetation.
It is difficult to prevent flies coming in through the doors the customers use, particularly if you have open doors. Consider whether you should have strip curtains on the doors. There should be an electronic fly killer in the customer area to try and catch any flies before they move to the range or preparation areas.
Fruit Flies can also be an issue. These can come into the shop on the potatoes. They multiply rapidly and can be seen in the air. They can then contaminate packaging or product. It is therefore important to check deliveries thoroughly to make sure you are not bringing fruit flies, or any other pest issues in with deliveries.
You need to consider what you do about allowing dogs into the customer area, particularly guide dogs.
Pets should never be allowed into the premises or even encouraged to the external doors by feeding them scraps.
Waste is attractive to all usual pests, including birds. Outside bins should have close fitting lids and not allowed to be over full. They need emptying regularly and should be kept clean.