Asking if its wrong to charge 25 late fees to people on ssd when the rent is due on the 1rst and they don't get there checks until the 3rd?

No, its isn't unfair if that is in the rental contract that was signed. The people who signed it know what days their funds come in, and should have asked for the rent to be due on that day, or not signed the contract.

Thank you so much

Well there is a difference between wrong and illegal. If the lease specifies when the rent is due and what the late charges are, then its legal. If the tenant signed that lease, then they have no complaint.

If, however, they became disabled after they signed the lease, then it would seem a reasonable accommodation (that might even be covered under the ADA).

Have you spoken to the landlord? Tried to renegotiate?