I am a software engineer with 22 years of experience. When I called Authorize.net for more information about a "Returned Payment Fee" that suddenly appeared on our statement (and other hidden fees), the man I spoke with was extremely unprofessional, made comments referring to me as a "kindergartner", falsely claimed they have over 400,000 customers and said they don't need my business. He was condescending and belittled me. When I asked to speak with a supervisor, he placed me on hold for over 30 minutes (every few minutes you could hear a person breathing, then I would placed back on hold) until eventually the call was disconnected. After calling back several times, sending email and using their contact form, I finally reached a supervisor who said the fee was a mistake and gave me a credit. However this took considerable effort. Every time you communicate via email or their contact form, you will receive email up to three days later with typos, misspelled words and invalid (non-printable) characters. This probably indicates it's being answered overseas or via an automated system. Authorize.net caters to very small businesses and likely makes a large percentage of it's revenue from hidden fees, setup fees and penalties. We are now actively searching for a new gateway processor and do not recommend authorize.net.