There is no such a limit, But he wants to file return under Presumptive bases i.e ITR 4 then cash received through chaque is deemed income 6% on sales other wise 8% of sale , if wants to file ITR 3 and wants to disclouse NP below 8% or 6% Accordingly then no such a for sales in cash. but is expenses should be not more than 20000 in cash . otherwise expenses os disalowed .
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