Rent is quoted as if the property is occupied for 52 weeks. The property only pays for the weeks it is occupied — and the gap between the two is the most predictable surprise in property cash flow.
Advertised rent versus collected rent
When a property sits vacant, the rent stops and the interest does not. Two weeks of vacancy on a $650-a-week property is $1,300 of lost rent — roughly equivalent to the entire annual council and water bill for many properties. Investors who model 52 weeks of rent are modelling the best case, not the base case.
What drives vacancy
- Rental depth of the suburb. How many comparable leases transact in an average month. A suburb with thin renter demand has longer gaps between tenants.
- Property type and price point. The most rentable properties are those a durable renter cohort can actually afford and actually wants.
- Condition and presentation. A property that needs work takes longer to let and attracts a weaker tenant at a lower rent.
- Seasonality. Vacancy is not constant through the year; turnover clusters around the school and work calendar.
The cash math of vacancy
| Occupied weeks | Rent collected | Effective yield on $900,000 |
| 52 | $33,800 | 3.76% |
| 50 | $32,500 | 3.61% |
| 48 | $31,200 | 3.47% |
| 44 | $28,600 | 3.18% |
Illustrative. Four weeks of vacancy costs roughly $2,600 of rent and ~0.6% of effective yield on this example.
Model vacancy, then stress it
The HomeScope calculators treat occupied weeks as an input, not a fixed 52. Model the property at 48 weeks to see the weekly contribution when things are merely normal, and at 44 weeks to see the stress case. If the difference between the two changes your decision, vacancy was your real risk all along.
A cash buffer measured in months of the stressed weekly contribution — not the advertised rent — is the correct buffer for vacancy risk.