You don’t need a great microphone to sound good. While microphones vary from tens of dollars to tens of thousands of dollars, all of them are completely useless if your recording environment is unsuitable. Go soft or go home (or both!). Soft furnishings are key when it comes to recording voices. Your recording environment is the most important part of any audio content. I spend a lot of time treating badly recorded audio; the better you record at source, the better the audio will sound and the easier it will be to edit.
This may also include signed letters from employers. For example, my wife was also a 1099 employee at the time, as a nanny. Our lender asked for letters from her bosses stating that she was currently employed and would be for the foreseeable future. Depending on your situation, you many need a letter from your publisher. It just depends on how far down the rabbit hole they want to go.