According to this BBS post the cheats for the Pets expansion will be as follows:

boolprop ControlPets [on/off]
- Makes pets fully controlalble, but you can’t cancel actions from their queue

boolprop DisablePuppyKittenAging [true/false]
- Turns off aging for kittens and puppies

boolprop PetActionCancel [true/false]
- Normally, you can’t cancel actions in a pet’s queue, but this cheat makes those actions accessible

boolprop ShowCatalogePFlags[true/false]
- Activates labels in the detail view of each Buy mode and Build mode objects (except floor or wall coverings) to show which product they came from (EP or SP)

boolprop PetsFreeWill [true/false]
- Turns pet free will off.

DeleteAllAwnings
- Deletes all awnings on lot

DeleteAllFences
- Deletes all fences on lot

DeleteAllHalfWalls
- Deletes all half walls on lot

DeleteAllObjects [Doors/Windows/Stairs]
- Deletes all Doors, Windows or Stairs on lot

DeleteAllWalls
- Deletes all walls on lot

IndividualRoofSlopeAngle [15/75]
- Activates a tool to change the roof slopes of individual roofs on a lot

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