Audit is one of the critical subject in ca final group 1.
As per my experience you have to read module ( atleast highlighted portion ) + practice manual + 3 rtps latest.
Also refer short notes by Pankaj Garg from the beginning of your preparation. Amendments should be done.
Because if you see paper pattern, you will realise that no one stop solution is there, you have to refer required ICAI material appropriatly in a smart manner.
Pankaj Garg Book it covers entire PM.. However for manner of writing answer you have to check PM. still this book is good as entire SA questions of PM is covered in respective SA and same for other chapters too..go for it without 2nd thought. further there is also a facebook page on which he regularly post any amendments etc. so this will be a good combo.book + FB Page
You can refer Surbhi Bansal for CA Final Audit. It is the best book for self study.
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