It's easier to understand this web application when you think about a CMS (WordPress) or CRM (SugarCRM); the logic behind this system is very similar to those two. My PMS may offer fewer possibilities than those systems above, but it just does what I want it to do. Additionally, writing extensions is not too hard, depending on the logic required. Anyone with development knowledge can pretty much write their own extensions for personal needs. Keep a track of your personal goals. You can use...