Sales Audit

Dear friends are these sufficient procedures for Audit of Sales which I have to do in couple of days? Please let me know soon....

Nature of Product
Derive understanding of sales procedures
Check Internal Control Compliance (check auditors report last year for weaknesses)
Compare with last year's Sales
Types of sales cash, credit, credit cards
Check for duplicate vouchers
Check Number of units of products sold check with last year
Check Selling prices and compare with last year
Check Sales returns compare with last year
Check GP ratio compare with last year
Check COGS compare with last year
Check NP ratio compare with last year
Check credit limit checking compare with last year
Check for discounts allowed basis (cash/trade discounts)
Check all items above material limit (atleast 80%)
Check 20% (based on Pareto principle) of small items using random sampling)
Check with recognition criterion as per AS-9 are followed
Check for consignment sales whether wrongly included
Check for goods on approval basis whether wrongly included
Check for foreign exchange transactions
Check for free samples distributed
Note and check exceptions in samples and expand sampling as necessary based on sample results
Discuss exceptions with authorized personnel for explanations on differences