You are reviewing the work performed by Robert, a first-year auditor. Robert was in charge of detail testing the existence assertion of accounts payable related to purchases of supplies. The company receives the supplies with the invoice from the vendor and records an account payable. The balance of accounts payable as of September 30, 2021 was $540,000 (it consisted of 10 large payables, totaling $540,000); the overall materiality is $150,000 and the performance materiality is $100,000. Robert's documentation is as follows:

"I took all invoices from the purchasing manager and agreed them to the GL". Eight of the invoices matched with the GL, two did not:

Conclusion 1) Payable #A234 was recorded as $120,000, but the invoice was for $210,000. As such there was a $90,000 error. The error was below the $150,000 materiality threshold, thus deemed immaterial.

Conclusion 2) Payable #A723 was recorded as $7,000 instead of $27,000. As such there was a $20,000 error. The error was below the $150,000 materiality threshold, thus deemed immaterial.

Conclusion 3) Since neither error exceeded the $150,000 materiality threshold, we can be reasonably sure that the existence assertion of accounts payable is correct in all material respects. The aforementioned errors are noted and included in document #XYZ41.

Required: Based exclusively on Robert's documentation, are his procedures and conclusions correct? If yes, say so; if not - explain what the problem(s) is(are). (6 marks).