S.D Bala VS Study Material Halp

LEASING DECISION, WHICH METOD SHOULD BE FOLLOWED IN EXAM IN EVALUATIN THE BUY OR BORROW PROPOSAL, BECAUSE OF CONFLICTION IN STUDY MATERIAL AND S.D BALA SIR SOLUTION

1.In S.D.Bala sirs' book repayment of loan inst, and interest is not considered on the assumption that compounding  and discounting at the same rate will give same result, and therefore we need not to consider the int and repayment. ( it taken into consideration the whole cost of assets as a initial outflow) - [ this method take very less time to calculate NPV)

2. In study material, both repayment of loan and int element is considered at different point of time ( however Study material method is more logical but time consuming)

PLease suggest which method follow

whether S>D Bala books is exam oriented or not

Thanks in advance