I know of such template systems as Joomla, Drupal, Wordpress; I'm sure there are many other proprietary systems out there. My question to the forum is, when a client wants to get involved with a template system, are there technical/financial issues that they need to be alerted to. Some of the issues I've come across are as follows:
1. most systems require Php 5 or better and the latest mysql database
2. the template must be hosted by the company who is "selling" the template
3. the template is really not yours; usually you're just renting it; if you want to leave to another hosting service you can't do it.
4. add-ons can create extra fees, e.g. adding an ecommerce feature.