I have been running a community based joomla site for a number of years, however I am not a technical person. Therefore, I rely on sturdy extensions created by people who support their product. I have been using AdsManager for years. I love it. It's easy for user and administrator. Thomas Papin thinks through usability and supports his products. Recently I purchased and installed PaidSystem. It installed easily, but it had some conflicts. I wrote to support. Papin communicated with me. Answered several emails and solved all my issues within 2 days.
PaidSystem itself meets my needs perfectly to turn a free classified section into a partially paid solution. I'm very pleased with the results. Support from this company is excellent. Through the years I had a number of occasions to ask questions. I am always answered promptly and politely. Usually by Papin himself.