What you are getting for your money buying a module!
Here is what you are getting when you buy a module!
In the modules is the entire syllabus which you should use as study guide!
There is enough reference material, where you can lookup things you do not know/understand. - You do not need to buy any books at all!
You can also ask in case you do not understand a subject!
There are the entire sub-modules with some infos and exam questions for each subject, you can practice the sub-modules. One of the High-Lights are the "Brainstorm Files" where you are learning essentials that will appear in any exam by heart. There is a "final exam" which is using exam questions from a huge data-base, and changing exam questions each attempt.
You practice those until you are getting 3 times 90%, and you will master your exam