If you pass every step in single attempt then it doesn't cost much but if you take multiple attempts then this course is costly.
In every attempt there will be new changes in most of the subjects , you have to buy new books. Also need to do coaching of few subjects again.
The biggest cost is opportunity cost ,if anyone not clear within 4.5 to 5 years from cpt entrance date then extra time will cost you much .
No value addition in that extra time.
Evaluate your own position and then decide.
Work hard - study smartly and good guidance will make you C.A.