How can I prepare for CA inter costing GROUP 2 ?

for CA Inter costing its clear and all knows who is best teacher.......Gupta sir he has great knowledge about costing a very trusthworthy teacher 

for CA Inter mere according parag Gupta sir is best without any doubt tricks ke sath har cheez clear krte hai which is the bestest thing you can ask also to someone who cleared his Inter exam 

For CA Inter costing parag gupta sir is best his teaching skills are commendable i don't prefer any teacher for CA Inter costing