Hello,
I have been in the medical billing/coding profession for 23 years. I have worked in a physician's office, for a hospital, and own a billing co. The questions you have are good ones, but here are some other things you should consider. Do you know the doctor you are doing billing for? Do you know how he/she runs their practice? Are they ethical? I do not bill for clients that I do not know.
I have fired clients that commit fraud and the only way I knew they were committing fraud was I knew what they were telling me to bill and how to bill it was wrong. I guess what I want to tell you is this, know the rules, know who you are signing a contract with, know they are trustworthy. Visit their office frequently, what you hear going on there will amaze you. My client base is by word of mouth, one doc tells another. I personally know the docs I bill for. Can you mass market docs for billing, absolutely, would you trust them to know the rules and be ethical would be a better question. Your billing is only as good as your documentation. Are they documenting what they need to? How will you know? Would you blindly trust a doc to do his billing and never know his staff or know what kind of doctor he/she is? My answer is no. Consider not only the software/computers/office equipment/billing knowledge, but who you trust to have a relationship with.
Hope this helps some, I think people don't realize sometimes the full spectrum and the consequences of this business. I have billed from a hospital, an office and home. There is much to consider.