As far as I know in Australia, a disabled person can start a business similarly to any able-bodied person. Unless the disability affects someone's mental and reasoning capacity, s/he is free to register business name, Australian business number, register with the tax office for GST, etc... And operate a business. Please note I'm not a lawyer nor an accountant. I just studied business and commercial law years ago so I don't know if there's been any changes. Although i haven't come across legal obstacles relating to a person with disability legally starting a business.