Nothing overly state of the art. Between the health department requiring everything to be clean and a contract with an exterminator like Orkin, it’s not that hard.
Orkin will have bait stations inside and out and come in on a regular basis (once a month or more) to check and re-bait them as well as keep an eye on trouble spots (unreachable corners, under counters, crawlspaces, above walk in coolers, under sinks, behind stoves, HVAC vents, electrical chases etc. They’ll also make suggestion above and beyond what the health dept requires. Things like keeping food in air tight containers, moving the dumpsters further from the building, dumping water down unused floor drains (fruit flies), sealing up holes that rodents can use to get in etc…
The funny thing is, if there’s food, there are mice, the trick is keep them to a minimum and making sure the customers don’t see them. I, nor any of my employees have seen a mouse in our building in at least 10 years, yet every month the Orkin guy mentions “activity”, but mainly around the perimeter of the building.
For flies it’s just a matter of keeping food in the cooler and and closed up as much as possible, but the highest tech thing your going to find is those glowing purple UV lights you see on the wall. Nothing more then a glue trap inside there. The trick with those is not necessarily to trap the flies, but to interrupt their breeding cycle. The only thing we have a huge problem with in the summer is fruit flies. The best thing we’ve found to deal with them (and it hardly makes a scratch) and also seconded by the Orkin guy is a container of vinegar with a drop or two of soap and some little tiny holes in the lid. The fruit flies smell the vinegar, fly in and because of the soap, there’s no surface tension so when they try to land, they drown.
Oh, one other thing. When you walk in to the mall, you go through two doors. If between those two doors you felt a strong breeze blasting down on you, that’s called an air curtain. Helps keep the bugs out and the warm or cold air in.