Developing a residential block in Perth can cost around $20,000 to $40,000 in 2026 for siteworks alone. That's before adding building plans, council approvals, utility connections, or the cost of constructing your home. The challenge is that no two blocks come with exactly the same expenses. A flat, vacant block with easy access might need relatively little preparation. Another block just a few streets away could require extensive excavation, drainage or retaining walls. Here