What is the best book for ama ca final

For O R part refer to Mcgrawhills publication by Vohra.  For Costing part refer to Saxena & Vasishth.  Both these books can be used as reference books.

Primary books should be ICAI's Text & Practice Material.

Thanks!

Yes Vashisht and Saxena is a very comprehensive and good book, which requires you to spend considerable amount of time to cover the syllabus.