I am currently working with a disability attorney. I applied one time by myself, although with her guidance and was turned down. Then hired her and was promptly denied a second time. She now has requested an appeal which will get us an appt with a judge and that can take up to two years...so I'm not holding my breath.
As far as questions, I don't believe you need to have any. My attorney asked me everything she needed to know. I do know that I have had to gather information for her, which she told me what I needed...things like medical records, names, addresses and phone of every doctor I have seen in years and years, all meds I take, current salary and income for the past few years and proof of it. That's all I can remember right now. But don't worry over questions. Your attorney knows what is needed so he/she will prepare you.
Best of luck
Miriam