The content is very quantitative and logical; it is simple to grasp but may take a bit of grinding because most questions you'll encounter are very huge and may be overwhelming. Practice is very important in Cost Accounting, so it's one of the few subjects where the book isn't compulsory but I would recommend finding a PDF to grind questions on. The exam is moderate in difficulty.
The tests usually revolve around concepts covered in the previous weeks. The actual content can be somewhat challenging but should be fine if you've kept up with content.
However, I have a major bone to pick about the tutes/tests. Cheating is RAMPANT amongst students who take this subject. This is because many tutors do not give a fuck, and allow students to cheat easily. Many take pictures of the test and send it to their friends. They had to alter the questions between tutes this sem after the staff caught on. All in all it's a shitshow and poor effort from the coordinators, and unfair to the honest students. Try to get a tute with a lazy-looking tutor, and group with that scummy/lazy guy who's likely to cheat and give you the answers.