If your mother is on SSDI specifically and not SSI. Assets and unearned(passive and rental income) does not affect anything. She could buy a house, then buy 3 rental properties and as long as shes not managing them personally, they are considered unearned income and will NOT be held against her SSDI. There is no restrictions based on property. Donald Trump could recieve SSDI and still own all that rental real estate and collect the rent. Thats how the current law is setup. She should call and speak to a disability attorney, they should be able to explain all of this and answer all questions.