How Our AI Renovation Cost Estimator Works

Getting the renovation cost estimate right is the most critical — and most difficult — part of evaluating a flip property. Underestimate and you wipe out your profit. Overestimate and you pass on a great deal. We use a two-stage process: AI photo analysis followed by structured cost modelling.

Stage 1: AI Photo Analysis

Every listing photo is sent to an AI vision model. The model evaluates each image across a structured set of renovation indicators:

• Roof condition (visible sagging, missing tiles, age of material)
• Exterior cladding condition and paint state
• Interior finish quality and age
• Kitchen condition — bench material, appliance age, layout
• Bathroom condition — fixtures, tiles, ventilation
• Flooring type and condition
• Structural concerns (visible cracks, moisture damage, unlevel floors)

From this assessment, the model assigns an overall renovation level: light (cosmetic only), moderate (kitchen/bath + cosmetic), or heavy (structural + full interior). It also flags specific high-cost items like re-roofing or full kitchen replacement.

Stage 2: Cost Modelling

Once the renovation level is established, we apply a per-square-metre cost rate to the property's floor area. These rates are calibrated against NZ build cost data and updated periodically to reflect materials and labour market conditions.

Line-Item Additions

Beyond the base rate, specific high-cost items are added individually when flagged by the vision analysis. These include full kitchen replacement ($25,000–$45,000), bathroom replacement ($12,000–$22,000), re-roofing ($20,000–$60,000 depending on size), and re-piling ($15,000–$40,000).

Limitations and How to Use This Data

Our estimates are designed for initial screening, not final budgeting. They work best when photos are comprehensive and of good quality. Properties with few photos, or where the agent has deliberately avoided showing problem areas, will have lower confidence scores. We always recommend a professional building inspection before making an offer.

“Think of the AI estimate as a 'good enough to shortlist' number. Once you've shortlisted, bring in a quantity surveyor or experienced builder for a proper scope.”

Scenario Modelling

On every property detail page, you can override the renovation cost estimate with your own figure and immediately see how it impacts the flip ROI and rental yield. This lets you stress-test deals quickly — for example, what happens if renovation runs 20% over budget?