How does a Currently Qualified Disabled Person Terminate Benefits

My Son is a high functioning adult with Autism. He was approved for SSI when he turned 18. It has been a nightmare of endless paperwork and mistakes that the SSA has buried us in. As he Payee and being responsible for reporting everything on his behalf I cannot imagine how the disabled and the undereducated can navigate the paperwork heel the SSA minions create for the disabled that are striving hard for their independence and not rely on SSI to support themselves. Between never getting him set up for Ticket to work program waivers towards his monthly income, to being a college student, to working part time we have seen it all with the mistaken over payments and the hostile demands for repayment sometimes in the form of no payment months without fully explaining how they calculated the error and or corrections to resurrecting past over-payments that were supposed to have been wavered based on requests for waiver and administrative judge reviews that never get seen ever by anyone leading to a continued demand for payment and a threat to attach any tax return you might have as a result of actually having the audacity to work. We have helped our son heavily to help him achieve independence and he now works full time while going to school part time... he wants to be OFF the SSI's program, does anyone know how we/he goes about doing this.... this has been a complete disaster and what we have learned is you just plain do not want the government involved in your life in anyway. shape or form..... EVER!