Anyone buying commercial real estate needs to have a thorough understanding of the local zoning regulations. These will dictate what you can and cannot do in a particular area, which in turn could influence whether or not you can establish the business you want there.
Sometimes the local authorities do not seem to offer much leeway when it comes to certain zones. They would prefer to keep a particular street, set of streets or wider area exclusively for certain activities.
One example might be a residential area of town. The authorities probably want it to be a place where children can play in the street and people can breathe clean air. So they are unlikely to to let a warehouse that requires big trucks coming in and out day and night move into that zone. On the other hand, they might well allow someone to set up a school or small grocery store or coffee shop there.
What if an exception to the rule is already there?
Maybe there is a warehouse already in that section of town. Maybe a few trucks do roll along the streets, despite the children living there. Does that mean the authorities will make an exception for you if you wish to set up a new warehouse there? Not necessarily.
Maybe the warehouse was there before the houses sprang up and that is why it is allowed to stay. Or perhaps the owner managed to get the authorities to give them a zoning variance for reasons you do not fully understand.
One business having a zoning variance does not in any way mean you will be given one if you were to apply. Learning more about your options is wise if you think you have found a piece of real estate to site your business on, but are unsure whether you will be allowed.