SMALL BUSINESS SYSTEM
OWNED BUSINESS CROSSOVERS/UPDATES
Business Items - Various decorative signs and decals are cross-pack, so you could use a DO decal on your new B&H sign if you wish, or vice versa. Functional Open/Close signs from B&H do not work for other business types, and default to the Closed image if placed decoratively.
Retail [GTW] - You cannot live on Retail lots. Various sales displays and surfaces have been updated to work like the ones in B&H when placed on Small Business lots, including the bakery and ice display cases, display shelves and pedestals. Mannequins don't seem to work for sales, but Sims will Try On Outfits from them if you have that set as a Business Activity.
Restaurants [DO] - You cannot live on Restaurant lots. You can use the Chef Station as a standard stove, or hire Caterers (not Chefs) on it, but it seems to be missing some newer stove interactions like Canning [CoL] and Family Recipes [B&H]. Sims cannot order food like they would at a Restaurant, but with the pack can eat via Counter Service (like Cafés) or help themselves to food that is not set for sale.
Vet Clinics [C&D] - You cannot live on Vet Clinic Lots. Vet examination/surgery/lab objects can be used on Small Businesses (to make pet treats, cure pets and train the Veterinary skill), but there are no Business Activities, nor Employee Tasks that direct Sims to use them autonomously. The pet treat vending machine can be filled with treats on Small Businesses, and looks full, but Customers visiting the lot cannot buy from it. You CAN give/attend Classes/Lectures for the Veterinary skill via the Hobby Whiteboard, so you could have a Vet School, for example.