I file & prepare my Mom's (for her business as well), my brother's (for his business as well), my sister's, her boyfriend's, my mom's little japanese old lady friend whose husband died 2 years ago and doesn't trust her kids to do it, my mom's neighbors across the street, and my taxes. Various years other peoples get added on (boyfriends, friends, whatever).

It's fairly straight forward, if I have questions about anything, I just read the appropriate IRS documentation, and I use turbo tax. I've been doing it for years and haven't had a problem.

Of course, none of the above people have ever been appointed to public office requiring the congress to go over their tax returns.