Sampling Method
MUS is standard for substantive overstatement testing. Classical is used when items are similar in size or when testing for understatement.
↳ ISA 530.A4 — items are selected proportional to their monetary value. Larger items have a higher probability of selection. Standard for overstatement testing.
Confidence Level
Reflects the assessed risk of material misstatement. Higher confidence = larger sample.
↳ Risk of incorrect acceptance: 10%. Confidence factor (CF): 2.31.
Population & Materiality
Enter the total monetary value of the population being sampled and the materiality thresholds from your planning.
Total monetary value of the account or class of transactions
Typically performance materiality or a fraction of it
Prior year misstatements or current estimate. Leave blank or enter 0 if none.
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Sampling Considerations for Real Estate
Real estate audits combine property-level valuations (which may be tested individually for large portfolios or sampled for very large ones) with high-volume tenant transactions. Rental income, service charges, and lease incentive amortisation all require testing across a population of tenant leases that can number from dozens to thousands depending on portfolio size.
Sampling focus: Real Estate
Rental income sampling should trace from lease agreements through to cash receipts. MUS applied to the annual rental population by tenant naturally selects the largest tenants. For property valuations under IAS 40, where the portfolio is too large for 100% testing, sampling properties and testing the valuation inputs (yield, ERV, vacancy assumptions) is the standard approach.
Key sampling considerations
For investment property portfolios with fewer than 30–40 properties, consider testing all valuations individually rather than sampling — the population may be too concentrated for statistical sampling to be meaningful. Rental income should be tested against signed lease agreements — sample tenancies to verify contracted rents, rent-free periods, stepped rents, and break clause provisions. Service charge income and expenditure should be sampled separately — test that charges to tenants are supported by actual costs incurred and that reconciliations are performed. Lease incentives (rent-free periods, tenant improvement contributions) must be amortised over the lease term — sample leases with incentives to verify the amortisation calculation. For development properties held as inventory, sample cost accumulations to verify that only directly attributable costs and qualifying borrowing costs are capitalised.
ISA 530.5 — Audit sampling means applying audit procedures to less than 100% of items within a population so that all sampling units have a chance of selection.
ISA 530.A4 — MUS uses monetary units as the sampling unit, giving each monetary unit an equal probability of selection.
ISA 530.A11 — Sample size is affected by the tolerable misstatement, expected misstatement, and the required level of confidence.