I applied for SS disability without the help of an attorney. Since you have already submitted the paper work, most of the work is done. In my opinion, the written application is the MOST important part of the application...YOU are totally, 100% responsible for how you represent yourself to SS. They never interview you. They only read what your wrote.
I had two doctor interviews. They form their own opinions of your condition. These doctors are under contract to do these evaluations. My surgeon was contacted for a report. These responses are out of your control. That is why YOUR written application is so important.
You have to understand what SS means by disabled...unable to do ANY job or, you are within 6 months of death (reader's digest version). If you have demonstrated that in your written application and your doctor evaluation agrees, you will probably be approved. I went back to work as a self employed person but it was too dangerous for me to work by myself. I took months of rehab trying to correct my balance...I really wanted to continue working...but I still have balance issues 4 years after my surgery. I was 60 years old when I was approved and my age was probably a benefit.
The income is based on the standard SS tables. In my case, it did not come even close to what I was earning, and I could not live on that disability income. Fortunately I was close to retirement and had done all of the correct things to retire, so it worked okay for me. On your second anniversary you are enrolled in medicare and that is deducted from your disability. You also pay taxes on the SS income but not social security, leaving you very little in your check book.
If you get denied approval, it is almost impossible to get approved on the second time around. It would be best to get an attorney if you are not approved. The application takes abut 6 months to go through the system. Hope this answered some of your questions. Ask, if you have more questions.
James