Investment approach
Developing a Plot: How to Work Out the Economics
Development economics is revenue minus every cost from buying the land to the sale, followed by a check of the cushion: how far price or budget can be wrong before the profit disappears.
The economics of developing a plot are worked out as sale revenue minus all costs from buying the land to the last sale, and then the cushion is checked. The cushion shows by how many percent the sale price can fall, or the construction cost rise, before profit becomes zero. Below is a worked example with round numbers: it is not a forecast and not the figures of a real project.
What the budget is made of
Assumptions of the worked example: a plot in sòl urbà consolidat (consolidated urban land), already solar (serviced and buildable), bought from a private individual, 1,000 m² of construction of which 800 m² is saleable area, 3.5 years from purchase to sale. All amounts exclude IVA (Spanish VAT).
| Item | Assumption | Amount, € |
|---|---|---|
| Plot | Purchase price | 1,200,000 |
| ITP | Catalonia scale on 1.2 M€ | 129,000 |
| Notary and registry | 1% (assumption) | 12,000 |
| Project, licences, fees | Assumption | 150,000 |
| ICIO | 3% of the cost of works, rate set by the ayuntamiento | 54,000 |
| Construction | 1,000 m² at 1,800 € | 1,800,000 |
| Contingency | 5% of construction | 90,000 |
| Insurance, supervision, other | Assumption | 100,000 |
| Selling costs | 3% of revenue | 132,000 |
| Total costs | 3,667,000 | |
| Revenue | 800 m² at 5,500 € | 4,400,000 |
ITP (the property transfer tax) is calculated on the scale in force in Catalonia since 27 June 2025: 10% on the first 600,000 €, 11% on the next 300,000 € and 12% on the remaining 300,000 € (Agència Tributària de Catalunya). The ICIO tax (municipal construction tax) accrues when work starts, and its rate cannot exceed 4% (art. 102 RDLeg 2/2004).
What the calculation shows
The project's profit before corporate income tax, before loan interest and before division between the participants is 733,000 €. That is 20% of costs. If all the costs are assumed to go in at the start and the revenue arrives 3.5 years later, this is about 5.3% a year compounded. With staged investment the figure is higher, but it depends on a payment schedule that the example does not have. A 20% margin on cost is not 20% a year, and the two must not be confused.
The break-even point is a price of 4,555 € per m². That is 17% below the assumed price. If sale prices turn out 17% lower, profit will be zero.
How profit reacts to mistakes
The table shows profit in thousands of euros and margin on cost as the sale price and the construction cost change.
| Sale price \ Construction | −10% | Base | +10% |
|---|---|---|---|
| −10% | 501 (14.5%) | 306 (8.4%) | 112 (2.9%) |
| Base | 927 (26.7%) | 733 (20.0%) | 539 (13.9%) |
| +10% | 1,354 (38.8%) | 1,160 (31.5%) | 965 (24.9%) |
A 10% fall in price and a 10% rise in construction cost at the same time leave 112,000 € of profit, or 2.9% on cost. This case shows the main point: the sale price matters more than the budget, because revenue is 2.4 times the construction cost.
A delay costs money too. If the sale slips by 6 months and holding the asset costs 20,000 € for the half-year, profit falls to 713,000 € and the annual return on the same basis to 4.5%. A one-year delay gives 693,000 € and 3.9%. Profit suffers little, the annual return noticeably.
What the worked example simplifies
The example does not include loan interest, corporate income tax, sales in phases or licence risk. What needs to be added in a real calculation:
- Plot price and tax. If the seller is a business, IVA at 21% and AJD (stamp duty on legal documents) are paid instead of ITP (see the article on land plot investment). Recovery of input IVA and its timing should be discussed with an asesor fiscal (tax adviser).
- Urbanisation and cessions. In sòl urbà no consolidat (non-consolidated urban land) the owner pays for urbanisation and cedes land (art. 43–44 Llei d'urbanisme, the Catalan Urban Planning Law). More in the article on the owner's obligations.
- The protected housing share. Since 1 January 2026 the plan reserves land for protected housing at 40% of the residential floor area of the development in sòl urbà no consolidat and 50% in sòl urbanitzable (developable land) (art. 57.3 Llei d'urbanisme); plans approved before that date have a transitional regime.
- IVA on construction and sale. A contract to build housing and the sale of new housing are subject to IVA at the reduced rate of 10% (art. 91 Ley 37/1992).
- Sales schedule and buyers' advances. See the phases of residential development.
Who this model does not suit
Plot development does not suit anyone unwilling to accept price risk: a 17% cushion in the example looks solid until the market moves further. It does not suit someone who needs liquidity either: the money is tied up for years. The weak point of the calculation is that the sale price comes from an assumption, not from a contract.
Next step: put your own numbers into the investor calculator and check the assumptions against the calculation methodology. How exactly the project's profit is divided between the investor and DNPI is fixed by the contract for the specific project.
Questions and answers
What margin counts as normal for plot development?
There is no single figure, and I will not give one without a source. The cushion matters more: how far price or budget can be wrong before zero. In the worked example it is 17% on the sale price.
How does margin on cost differ from annual return?
Margin measures the profit of the whole project against costs. Annual return takes the term into account: in the example a 20% margin over 3.5 years corresponds to about 5.3% a year, if all the costs go in at the start. With staged investment the figure is higher.
What affects development profit the most?
The sale price, because revenue is larger than construction cost. In the example a 10% fall in price cuts profit by 427,000 €, and a 10% rise in construction cost cuts it by 194,000 €.
Is IVA included in the calculation?
The worked example uses amounts without IVA. A developer usually recovers input IVA through a deduction, but the conditions and timing are determined by an asesor fiscal.
