It's differs slightly for each embassy. The workstream is harder to get than say cooking or muay thai soft power, but it's worth it. I did mine myself via London embassy and it was no walk in the park. If you are legit then you should have no issues.
same, arrived a few days ago and they didn’t even care about the old passport, I won’t bring next time extra fear crap from health & safety officers in this group 😛
They want to know you are legit and paying taxes. Try to formalise and show that you do this. I don't know stipulations for that embassy but meeting the criteria for London was very hard, I had to supply alot of difficult paper work. Give them as much as you can!