Presumptive taxation exclusions clarify which businesses and receipts are ineligible under the scheme, affecting turnover-based eligibility. Presumptive taxation under section 44AD excludes businesses of plying, hiring or leasing goods carriages covered by section 44AE, agency businesses, income in the nature of commission or brokerage, and businesses whose total turnover or gross receipts exceed the statutory threshold; a higher turnover ceiling applies where cash receipts do not exceed five percent of turnover, and non-account-payee cheques or drafts count as cash for that test. Professionals under section 44AA(1) are also ineligible.