If a small business has an office in a large building, it’s quite likely that the large building already has automation options that they could use.
If they have their office in something like a strip mall, as many real estate brokers and dentists and CPAs do, the landlord probably doesn’t provide anything.
In that case, for the kind of set ups you’re describing, it’s usually easiest just to get a dumb Lutron system. These are extremely reliable, work very well, and will generally cost less than a SmartThings setup. For example, I have an $18 lutron dumb occupancy switch In my laundry room. Anytime someone walks into that area after dark, the light comes on and it stays on until there have been several minutes of inactivity. It works really well and I don’t need it integrated with anything else.
As far as the air-conditioner, it depends on the brand and model, but there are a lot of options, which again would not require a SmartThings.
One of the important issues to remember is that commercial buildings have significant liability and regulatory requirements that DIY residential products do not. Air-conditioner controls will have to be ADA compliant, just as one example.
If the lights in the bathroom go out unexpectedly and someone slips and falls, the business is going to be liable for hundreds of times more dollars than you might have saved by putting in an inexpensive residential system. Remember also that commercial buildings generally have lots of people coming through them who are not particularly Familiar with the building Layout or the operational controls.
Because of these issues, It’s quite likely that any automation system you’re putting in will have to be approved by the business’ insurance company for liability purposes. A commercial lutron system will likely already be on the insurance company’s list of approved systems. A SmartThings system definitely will not be. (The system may possibly also have to be approved by the landlord, since they have some shared liability with the tenant.)
So if you’re talking about the US, it’s just not very likely that a SmartThings-based system will be a good fit to a commercial building, and there are already lots of other competitors that will be.
Are you thinking about this for a business that you yourself operate? If so, talk to your insurance agent and check your lease.
If you’re thinking about providing this as an installer product, again talk to your own insurance agent, but I just don’t think it’s viable in most jurisdictions.