If you already have experience, or some knowledge of how WordPress works then you'll find the initial setup and configuration a lot easier than someone who hasn't. However, having said this, I personally believe if you quite confident with exploring new platforms you will pick up on both WordPress and ClassiPress quite easily.
You do not need to be a coder in order to use either WordPress or ClassiPress, and the theme itself has all the functions built into it. Sure, if you want to make changes to the default theme, then you can look at learning new skills along the way, but essentially, you don't have to do that.
In short, a beginner who can follow instructions could capably install WordPress, install ClassiPress and run a Classifieds Ad website straight out of the box. This is exactly how I myself was introduced to ClassiPress/AppThemes :)
You may find it helpful to read some of our
documentation to get a feel for what is involved with the setup. Even better, if you have never used WordPress before, you can get a feel for how that works before you start even paying for a host by setting up a free
WordPress.com account and look around the admin, learn how to change the theme etc. (Just bear in mind you can't set up the ClassiPress theme on the free WordPress blog as they do not allow you to upload any theme of your own)..
Hope that information helps :)