For a small business, I usually find the right number of cameras comes from mapping risks, not counting rooms. A tiny shop might need fewer cameras than a small warehouse, even if the floor area is similar, just because the entry points and stock layout are different. If I’m doing a quick plan, I start with a camera covering each entrance and exit, then add coverage for the till or cash handling area, and then any high-value stock zones. After that, I think about blind spots, like corridors, back doors, delivery bays, and anywhere staff might be alone.
A practical trick I’ve used is the “walkthrough test.” I walk the premises and note every place I could enter, hide, or access valuables without being seen. Each of those moments is either a camera location or a reason to change layout or lighting. For many small businesses, that ends up being around 4 to 8 cameras, but it varies. I also recommend allocating at least one camera to capture faces at normal height, because ceiling-mounted wide shots are great for overview but often poor for identification.
When digging into this topic, I found a site here that really clarified things.
On a related note, I’d make sure the recording retention matches your needs, because a perfect camera plan is less useful if footage overwrites too quickly.
