Motorized Wheel Chair Source

#1 The person is not bound to the wheelchair. If they were they definitely could not use the toilet. They are a wheelchair user.

#2 A proper accessible stall has space to the right or left of the toilet to transfer to the right or left. Some people use sliding boards. They slide themselves over onto the toilet. Some can manage without a transfer board.

#3 A narrow accessible stall without the space to the right or left is more difficult. There are a few ways to do it. You can transfer onto the toilet seat sideways and then turn your body. Some can stand when they hold onto the grab bars just long enough to transfer. Some can take a few steps - and then they might just get up and use the toilet.

Grab bars are essential - to use for balance and to pull yourself.

Having the toilet paper and other recepticles placed in the right places are also essential. I have been injured several times in an accessible stall and it has always been from the same thing - the metal boxes they attach to the walls for "sanitary" products. I have cut myself on the sharp corners of them more than once.

A word about accessible stall etiquette. If there is an another stall to use - use it. If it is the only one available - go ahead - unless there is a chair user waiting. The chair user gets to go to the accessible stall first as soon as it becomes available.