I haven’t helped by son, who lives with us, apply for SSI yet. I’ve been researching how to document in-kind support and maintenance (ISM) he would pay from what he earns to make him eligible. I thought the following article was useful in explaining it. It recommends a:
written rental agreement, covering the individual’s proportional share of household operating expenses and, if applicable, food
It suggests using an ABLE account to pay for food and housing expenses.
Avoiding SSI Reductions When An Adult With Disabilities Lives With Family