A portable folding support structure for safely tethering an individual comprises a portable cart sized to fit through a residential doorway, having wheels and a motor that actuates at least one of the wheels. A hand-operated throttle and steering device control the cart. The cart comprises an extendable anchoring plate to prevent rolling. A substantially horizontal jib with the cart comprises a harness point for receiving a safety cable to which an individual is attached to allow safe cleaning practices and to minimize fall risk. A foldable outrigger provides stability to the cart and an anchoring pad attaches to a distal region of the outrigger to promote stability. A textile liquid-absorbing surface is positionable about an outer surface of a glass balcony to inhibit cleaning liquids from spilling below the level of the liquid-absorbing surface.