Substantive sales testing

If a company receives money, then you need to know where that’s come from: could be a loan, could be money laundering. Tracing invoices to/from cash receipts is evidence that the sale was real and also explains the receipt of cash. I assume that 1 is tracing to the cash book and 2 is tracing to the bank statement. Again, you expect consistency within a transaction: a Dr to the cash book should be traceable to the bank statement. Otherwise a company could fraudulently manufacture sales: fake invoices and fake Dr to cash book. It’s harder to fake cash going into the bank too.