CERT is the base/core so always refer it, apart from that also refer previous year question papers. It will give you idea about the level of question asked and you can prepare accordingly
But most important is rather than going for materials of different coaching institutes go for any one and complete the full syllabus. Often student try different materials/books and syllabus is left incomplete or last few chapters are covered in hurry.
PS: HC Verma is very Good book best suited for Engineering Entrance Exams, I will not suggest you for NEET.
So, plan before you start your preparation. you go through “M-learning video course”.M-learning also brings strong portability by replacing books and notes with small devices, filled with tailored .It is important to bring new technology into the classroom. “M-learning India” is one of the best online education platform for all the students preparing for the neet or aiims. The video lectures are so much informative and helpful.