Deep-dive guide
Land Share and Apartment Swap Simulator: What Does a Build-for-Share Deal Leave the Developer?
Executive industry analysis
A build-for-share deal looks elegant: the landowner supplies the plot, the developer supplies the building, and both split the finished apartments. No one needs to find a large sum for the land. But the elegance hides a thin margin. The developer funds every brick before a single unit is sold, the landowner's share is fixed by contract while costs and prices are not, and the whole deal depends on the gap between the sale price and the cost of building.
The structure of the problem is a ratio of two numbers that both move. Revenue is the area the developer keeps times the price per square metre. Cost is the gross built area times the cost per square metre, plus the financing, overhead and fees around it. A higher landowner share reduces the area to sell but not the area to build, so each point of share lowers revenue while cost stays the same. That is why the share is the most negotiated and most dangerous number.
The domino model follows the project. A larger share leaves the developer with less sellable area. That reduces revenue. Revenue is then compared with the construction burden, the share of it consumed by building and escalation, which sets the project margin. The margin, spread over the actual length of the project, gives the average monthly profit. A delay stretches the months, adds interest, raises costs and cuts the monthly figure from both sides.
The iceberg separates the visible build cost and the units handed over from the costs nobody quotes. Below the waterline sit the cost of capital during the delay, the rise in build prices while the project is late, the site overhead that runs every month and the transfer taxes, commission and developer overhead. Use the simulator to find the sale price, share or delay at which the deal breaks even, then decide how to renegotiate or restructure it.
Formula and methodology blueprint
The model returns the average monthly profit over the life of the project, which is eighteen planned months plus any delay. Sellable area is 82% of an 1,800 square metre gross build. The developer sells the part not given to the landowner. Costs include construction, overhead of 3% of build cost, transfer taxes of 4% of the land value, a sales commission of 2% of revenue, a financing cost of 1% a month on 80% of build cost for each month of delay, a build-cost rise of 0.6% a month of delay and a site overhead each month.
- Developer's area
- A = 1,800 × 0.82 × (1 − share)
- The sellable floor area the developer keeps after handing the landowner their share.
- Revenue
- R = A × price per sqm
- Total sales of the developer's units.
- Build burden
- (build + escalation) ÷ R
- Share of revenue consumed by construction and cost rises. Above about 80% the margin is thin.
- Project profit
- P = R − build − escalation − finance − overhead − site − fees
- Everything left after all costs over the whole project.
- Average monthly profit
- Net = P ÷ (18 + delay)
- The headline result. The breaking price or delay is where this reaches zero.
Cascading elasticity
The sale price is the most elastic input because revenue is its direct multiple while costs stay fixed: a ten percent fall in price removes ten percent of revenue and most of that falls straight through to profit. The landowner's share works the same way through area. Construction cost is linear. Delay is the sneakiest input, because it adds cost, shrinks the monthly average and raises the risk that the market moves against you.
Three real-world case studies
Bootstrapped starter
A small plot with a modest share
A small developer takes a cheap plot and agrees a share below the usual level, builds at a sensible cost and delivers almost on time. Margins are comfortable. Load it to see how a good plot and a fair share leave real room for profit.
Scaling mid-market
A prime plot in a strong market
A larger developer works a valuable plot in a strong market with high sale prices and reasonable costs. Costs are high in absolute terms but revenue is much higher. Load it to see how scale and price make the deal very profitable.
Black-swan crisis
A generous share and a long delay
A developer gives the landowner more than half the units, prices fall and construction costs rise, and permits delay the project by more than a year. Interest and escalation pile up. Load it to see how a deal that looked fair loses money every month.
Industry benchmark matrix
| Metric | Danger zone | Industry average | Top 10% elite |
|---|---|---|---|
| Landowner share of units | Above 55% | 35–45% | Below 35% |
| Build cost as share of revenue | Above 80% | 55–70% | Below 55% |
| Project margin on revenue | Below 8% | 12–20% | Above 25% |
| Delay beyond plan | Above 9 months | 0–4 months | None |
| Sale price vs build cost per sqm | Below 2× | 2.5–3.5× | Above 4× |
Variables and levers
Land value
Market value of the plot. It does not enter as cash, but transfer taxes and fees are charged on it.
Lever: Check the transfer taxes and fees due on the land before signing, and agree who pays them, since they rise with the land value.
Landowner's share of units
Share of the sellable floor area handed to the landowner in exchange for the land.
Lever: Negotiate the share against realistic margins, and consider a lower share plus some cash, or a staged share that depends on the sales achieved.
Sale price per square metre
Average price you expect to achieve for finished units, after negotiation and incentives.
Lever: Test prices against recent sales of comparable units, and avoid presales that lock a low price when the market is rising.
Construction cost per square metre
All-in build cost per square metre of gross built area, including materials, labour and permits.
Lever: Fix the build price with a competitive tender and a clear specification, with penalties for late or changed work.
Delay beyond plan
Months by which the project runs late against the planned eighteen months of build and sales.
Lever: Secure permits and utilities before starting, add a delay clause to the contract and keep a buffer, because each late month costs interest, escalation and site overhead.
How to use this simulator
- 1Enter the plot value and the share agreed or proposed to the landowner.
- 2Set the sale price and the construction cost per square metre from recent comparable figures.
- 3Add a realistic delay, because most projects run late.
- 4Press Find my breaking point to see which input ends the profit soonest.
- 5Compare with the fixed-price plan in the Parallel universe tab and share the link.
Mistakes to avoid
- Treating the land as free. No cash changes hands, but you pay it in units, transfer taxes and fees.
- Using today's sale price for a project that sells in two years. Prices move, and presales can lock in a low figure.
- Planning with zero delay. Permits, utilities and weather make delay normal, and each month is expensive.
- Agreeing a share from the plot's value alone. The share must also fit the project margin, otherwise the deal is unfinishable.
Frequently asked questions
What is a build-for-share deal?
The landowner transfers the land to a developer, who builds and gives the landowner an agreed share of the finished units. The developer keeps and sells the rest. Details differ by country, so check local rules.
Why is the landowner's share so important?
The share reduces the developer's sellable area without reducing the building cost. Each extra point of share removes revenue but not cost.
Does the model cover the landowner's side?
No. It shows the developer's result. For the landowner, the share times the area times price is the key value; lower developer margin raises the risk the project is never finished.
What about taxes and legal rules?
The model uses a flat transfer tax. Real taxes, permits and contract rules vary and change, so check current rules with a lawyer and tax adviser.
How do I find the breaking point?
Press Find my breaking point. The tool moves each input towards its worse end in a thousand steps and reports the value at which the average monthly profit reaches zero.
How accurate is this?
It is an educational model with stated assumptions, not financial or legal advice. Real projects need a detailed budget.
This is an educational planning model with stated assumptions. It is not financial, tax or legal advice. Replace the inputs with your own figures and verify important decisions with a qualified professional.