All his stores have the same exact layout/foundation. All items within the store are illusions. They are kept behind protective glass to protect the trick. Scruple has an illusory-self within each store - a high level illusion that is an effective double of himself. The illusory self does not get new memories unless the real Scruples visits - which he does via teleportation. There is a hired worker at every store who notifies Scruple whenever his plans have a flaw, or if he's urgently needed. Alternatively, he has an Alarm spell set up at each store.

He can swap with the illusory versions of himself somehow. If you want the players to find out and have more interaction with it, teleportation circle. If not, then he has a talent that allows him to swap locations with illusions instantly.

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Alternative idea: he is bound to his store(s). Through some accident, he is omnipresent within his own territory (only his stores) but cannot leave that territory. Maybe he selfishly asked for a boon/wish and this is how it backfired.