The provision strictly strict from giving any excuses for not maintaining any bill books. However in case of small time retailer with his or her annual turnover of less than 40 lakhs. Then that retailer is permitted to declare his annual income on pre assumption at 5 percent of actual sales under section 44AF. In that given case no books of accounts needs to be maintained. Same is applied for civil contractor under section 44AD in case 8 percent of the turnover is disclosed as profits. Even the transporters owing less than 10 goods carriage can avail the benefits of presumptive income schemes without maintaining the books of accounts. However if any persons declare the his or her income below the minimum level said under the scheme, it is mandatory for him/her to maintain the books and get them audited.