You really, really, really need to have a chat with the power company. That's the first step to avoiding expensive issues later.
Then, you need to have a long chat with your customer. Examine not just his use for the property, but whether his real 'business' is selling it off in a year or two.
Let me describe four similar installations I have seen:
Location "A" served a 'strip mall.' The original design 'cheated' by having one of the units also power the common spaces - a ploy to exploit the 'six disconnect rule.' Naturally, this became an issue later, when the new owner sought to change things.
Location "B" was served by an underground feed from a pole-mounted transformer platform. The CT enclosure was part of the main switchgear cabinet.
Location "C" was served by a ground-mounted transformer. In this case, the CT cabinet was at the transformer, and the switchgear at the building was little more than a disconnect switch and a breaker.
Finally, location "D" was designed as a simple light industrial unit, with provision to divide the space later. Well, that happened ... then another unit was added ... then another ... before you knew it, meter #6 was going up. All cobbled on to the original service.
Had the owner of "D" been honest about his plans, and spent a few more dollars, equipment would have been installed that allowed for ready expansion. Plus, the issue of six disconnects would have been avoided. Instead, the guy paid more- for a final mish-mash of equipment. Pay now, or pay later.
The requirement for a single utility meter serving the 6 200A feeders is rock solid here. Are you suggesting a CT Panel with a 1200 main Disconnect Safety Switch outside would be more cost effective since that approach would work here also????
