How townhouse economics differ from duplex

Three differences. (1) Scale economies on construction — per-m² rates can drop 5–10% vs. a duplex because you're amortising preliminaries, scaffolding, and site setup across more dwellings. (2) Marketing & selling — you can't sell 6 townhouses simultaneously to 6 separate owner-occupier families; presales are part of the play, and that means real estate commission per dwelling typically lands lower (1.8–2.2%) but campaign costs are higher ($25k–$50k for branding, signage, display marketing). (3) Finance — most lenders require ~30–50% presale coverage of debt before funding construction.

Strata vs Community Title vs Torrens — which to choose

Strata gives every dwelling shared common property (driveway, rubbish bay, possibly a shared garden) and an Owners Corporation. Community Title is rarer in NSW but allows shared facilities with individual lots. Torrens-title townhouses are uncommon at scale because each dwelling typically can't comply with subdivision minimum lot size — but where achievable, they sell at 5–8% premiums. The calculator below assumes strata by default; switch to Torrens if your site supports it. Strata adds DBP Act overhead if 4+ units are involved (then you're Class 2 in most cases).

Council contributions on townhouse developments

Section 7.11/7.12 developer contributions in NSW are typically $25k–$60k per dwelling for townhouse-scale developments, depending on the council. These cover roads, public open space, drainage, and stormwater upgrades attributable to your development's load. Affordable-housing levies may also apply in some inner Sydney LGAs (City of Sydney, Inner West). Confirm your specific contribution before lodging DA — most councils publish a contribution plan you can model against.

Presale strategy and finance gates

Most lenders require qualifying presale coverage before funding construction — typically 70–100% of the construction-loan tranche. So if your construction loan is $4M, you need $3.5M+ of qualifying presales (10% deposits exchanged on contracts with cooling-off expired). Qualifying presales include private buyers and some second-tier purchasers; off-the-plan investor sales often don't qualify. This is the single most common reason townhouse developments stall — finance approved subject to presales, presales not achieved, project sits in DA-approved limbo. Build a realistic presale program and price into it.