Dear Mr. Jha,
If assesse shows net profit below presumptive income of 8% then requred to maintain books and get audit of books.
But if total income is below taxable limit then assesse is not required to audit and maintain books.
The intention of the law here and meaning of "Total Income" is total income as per provisions of Sec.44AD i.e. on presumptive rate of 8%.
Thus for checking income below taxable limit, it is to check on the basis of presumptive income of 8%.
Law want to get releif from confusion that if net profit is below presumptive rate (whereas presumptive rate income itself is below taxable limit) no need to tax audit and maintain books.
Thanks.