This is a favorite of mine.

SMALL GARAGE:  Nothing physical added.  Just reskinned.

LARGE GARAGE: Reskinned completely (nothing left untouched) and added the following physical features:

• Trailers
• AI Truck/Trailer Parking
• ALL doors function
• Added second back door using idea from another garage mod I found online
• Added billboard by fuel area
• Imported signs from 2 other garage mods to better label the company
• Added lady to watch over the place (don;t let her innocence look fool you.  She is vicious)
• Added server farm to handle company data and framework
• Added and rearranged pictures from other garage mods
• Added vending machine for hot chocolate and other chocolate drinks (what?  I like chocolate!)
• Redid the outside fence to be iron instead of wood.
• Used .sii file from another garage mod to shorten garage door trigger distances.