Rental Yield Playbook for a 37m² Granny Flat

If your primary goal is rental income, you need a model that is simple enough to maintain but strict enough to challenge optimistic assumptions.

This playbook uses three layers: revenue, operating drag, and payback sensitivity.

1. Revenue baseline

Start with realistic weekly rent from comparable local listings, then multiply by 52 weeks.

Do not use peak asking rents as your default baseline.

2. Vacancy and operating drag

Apply a vacancy assumption and recurring costs:

• vacancy allowance,
• management/advertising costs,
• routine maintenance reserve,
• insurance and compliance-related costs.

Your net operating estimate should survive conservative assumptions.

3. Payback scenarios

Model at least three scenarios:

• base case: realistic rent and standard vacancy,
• conservative case: lower rent and higher vacancy,
• upside case: strong rent performance.

Compare each against your full project budget, not just unit price.

Example model structure

Decision checkpoints

Before paying major milestones, confirm:

• local rental demand consistency,
• target tenant profile,
• furnishing level vs. rent uplift,
• compliance and occupancy constraints,
• expected time-to-lease after completion.

Common yield mistakes

• Using top-of-market rent assumptions only.
• Ignoring vacancy and reletting periods.
• Excluding maintenance and compliance carry costs.
• Treating setup delays as zero-cost.

Practical next step

Pair this model with your approval and budget checklist. When revenue assumptions, approval risk, and total budget are visible in one view, decisions become much easier to defend.

If you share postcode and intended model, we can provide a scenario template to speed up your feasibility review.