An appraisal may not always apply depending on the loan. You may be considering an operating line of credit for example.
Also, I am not aware that there is a regulatory requirement to have an application with a commercial loan. My understanding of Reg B is that a lender should capture the intent of borrowers but it does not require an application.
Having said this, it is my strong preference to simply use an application as standard practice for documenting the intentions of businesses and people to apply for a credit. I mention this because you may come to a discussion of what is required by the regulation vs. what is a really good idea. My best advice is become very familiar with Reg B and FCRA.
You may also want to get a list together for items such as entity documents (article's of organization, etc.)