4 months advance rent but bad credit and work comps lawsuits

[Sai T.]

I have a unit for rent and I got the following from prospect tenant's agent. Please advise.

Quote

I have a mother and son looking to rent. Credit is shot due to her getting hurt at work and major problems with workman's comp, disability etc. He basically had to give up his life to care for her and his credit suffered. However, two of their law cases settled and they would be able to pay 4 months upfront in addition to first and security. He is working making decent money and she has a widow's pension and social security (I believe).

Would you be willing to consider them? I have their reports and its in high 500's/low 600's. She can provide a reference from current landlord. If so let me know UNQUOTE

I said to the agent rental unit is 2 story and it is not handicap-accessible. Agent replied 

"she has limitations but can deal with stairs when she has to"

I'm concerned if I rent they may find a reason to  sue me!