Our first build was some years ago on Joomla 1.5 and the free JEA estate agency component. This was kept going until 2017 when we migrated to a new site built on Joomla 3.x and the OS Property component. The main issues we faced or still face is the very frequent updates of Joomla and other components / plugins taking up too much time to implement. An update does not go by without something breaking on the site.

We are now on the latest build of Joomla - version 3.8.6