TD WEBSITE 4x5 (3).jpg
TD WEBSITE 4x5 (3).jpg

Property Development Feasibility Calculator

$55.00

A real-world assessment tool used by The Designory for in-house and client developments

This Property Development Feasibility Calculator is the exact spreadsheet The Designory uses to assess the viability of residential development projects — from dual occupancies and renovations to new builds and small-scale developments.

Built from practical experience (not theory), this tool is designed to help you understand whether a project stacks up before you commit time, capital, or emotion. It brings clarity to complex decisions by breaking a development down into its real components: revenue, acquisition costs, construction, consultants, holding costs, finance, and profit — both before and after finance.

If you’ve ever wondered “Is this site worth pursuing?” or “Where does the money actually go?” — this calculator is for you.

Who this is for

  • Property developers (new or experienced)

  • Homeowners considering a dual occupancy or subdivision

  • Renovators weighing up renovation vs rebuild

  • Designers, builders, and consultants assessing project viability

  • Anyone wanting to make informed property decisions

What’s included

  • One downloadable Excel (.xlsm) feasibility calculator

  • Built-in formulas and guidance notes

  • Flexible structure you can adapt to your project

  • Designed for Australian residential developments (GST, stamp duty, council costs included)

A real-world assessment tool used by The Designory for in-house and client developments

This Property Development Feasibility Calculator is the exact spreadsheet The Designory uses to assess the viability of residential development projects — from dual occupancies and renovations to new builds and small-scale developments.

Built from practical experience (not theory), this tool is designed to help you understand whether a project stacks up before you commit time, capital, or emotion. It brings clarity to complex decisions by breaking a development down into its real components: revenue, acquisition costs, construction, consultants, holding costs, finance, and profit — both before and after finance.

If you’ve ever wondered “Is this site worth pursuing?” or “Where does the money actually go?” — this calculator is for you.

Who this is for

  • Property developers (new or experienced)

  • Homeowners considering a dual occupancy or subdivision

  • Renovators weighing up renovation vs rebuild

  • Designers, builders, and consultants assessing project viability

  • Anyone wanting to make informed property decisions

What’s included

  • One downloadable Excel (.xlsm) feasibility calculator

  • Built-in formulas and guidance notes

  • Flexible structure you can adapt to your project

  • Designed for Australian residential developments (GST, stamp duty, council costs included)

What this calculator does

Why this tool is different

This is not a generic online calculator or simplified feasibility template.

It reflects how real projects are assessed — conservatively, methodically, and with enough detail to expose risk early. It forces you to account for costs that are often overlooked or underestimated, and it shows you how small changes in assumptions can dramatically affect profitability.

This is the same framework The Designory uses when:

  • assessing sites for development

  • advising clients on feasibility

  • pressure-testing renovation vs rebuild decisions

  • comparing multiple project scenarios

Important note

This calculator is a decision-making tool, not financial advice. All costs should be reviewed with your accountant, lender, and professional consultants before proceeding with a project. The accuracy of outputs depends on the accuracy of your inputs.

The Designory approach

We believe better projects come from better information. This calculator exists to remove guesswork, surface risk early, and help you design — and develop — with clarity.

If you’re serious about understanding whether a project works before you commit, this tool belongs in your toolkit.

This spreadsheet allows you to run a full development feasibility from start to finish, including:

  • Projected revenue

    • Multiple dwellings (lane, street, dual occupancy or more)

    • Flexible inputs for finished values

    • Net revenue calculations after selling costs and GST

  • Acquisition costs

    • Land purchase price

    • Stamp duty (percentage-based)

    • Buyer’s agent fees

    • Legal and conveyancing costs

  • Construction costs

    • New builds and renovations (per dwelling or $/m²)

    • Demolition

    • Home Owners Warranty Insurance (HOWI)

    • Contingency allowances (industry standard 10–20%)

    • Automatic subtotals and totals

  • Planning & consultant fees

    • Town planning

    • Surveying

    • BASIX / NatHERS

    • Architectural and interior design

    • Engineering (structural, hydraulic, geotechnical)

    • Bushfire and heritage consultants

  • Project management costs

    • Administration and bookkeeping

    • Monthly project management fees over the project duration

  • Finance & holding costs

    • Property and construction loans

    • LVR-based loan calculations

    • Interest rates and loan duration

    • Application fees, valuations, QS reports

    • Mortgage insurance and bank fees

  • Council fees & statutory charges

    • PCA and council fees

    • Long service levy

    • DA lodgement

    • Subdivision certification

    • Section 94 / development contributions (NSW)

  • Clear profit outputs

    • Profit before finance

    • Total costs including finance

    • Final profit post-finance

All formulas are already built in. You input your numbers — the calculator does the work.