When reviewing accounting estimates that are prepared by managemenT ...

When reviewing accounting estimates that are prepared by management perform, retrospective review of prior-period estimates to determine a possible bias.

And for any reason that you are using the work of a specialist, you may refer to the specialist in any audit report if you become aware of conditions causing substantial doubt about going concern. Do not imply a more thorough audit was performed. 

Some Review Engagement Procedures: 

• For Cash ask for compensating balances or restrictions on the availability of funds
• For Debt ask if assets have been pledged as collateral
• For AR ask if there has been proper cutoff for sales transactions
• For AP ask if all liabilities have been accrued
• For Fixed Assets ask if consignments were considered in the physical count 

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