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// WORKED EXAMPLETHE ARITHMETIC A DECISION RESTS ON

Profit on Cost: a Worked Example

The margin is the first loss. A lender wants to know how thick it is.

BY MICHAEL SHANG · SIXTEEN YEARS IN COMMERCIAL BANKING · UPDATED

// THE SHORT ANSWER

A developer quotes profit on cost to show a scheme is worth doing; a lender recomputes it to see how much of the plan has to go wrong before its loan is touched. The ratio itself is simple: the profit the scheme is expected to make, divided by everything it costs to deliver, land and finance included. The reading is not. It depends on what was counted as cost, whose sale prices were used, whether GST is in or out, and how long the profit takes to arrive, since a ratio with no time in it scores a two-year scheme and a four-year one alike.

BASIS  Practitioner judgment from sixteen years in commercial banking, set out in How Bankers Think (Highbank Press, 2026). Every borrower on this site is a composite constructed for teaching, not a client. The market is mid-market commercial lending as practised in New Zealand and Australia; where a convention differs elsewhere, the page says so.

// MAKE THE CALL

Issue 08 — Basalt Ridge Developments. A new-to-bank developer, a claimed 28% ROE and two other banks circling. Your bank has a growth target. Your call first, then the senior banker's.

Read the file →

// 01 — WHAT THE RATIO MEASURES

Every development has a margin between what it costs and what it sells for, and that margin is the first thing lost when prices fall or costs rise. Profit on cost measures it against the money going in. Below the margin sits the developer's equity, and below the equity the bank's loan, so the ratio tells a lender how much room there is before the losses reach the second layer, and from there the third.

Names vary. UK appraisals commonly quote profit on cost and profit on gross development value side by side; Australian feasibilities often speak of the margin on cost or development margin. The RICS standard on development valuation defines profit on cost as profit as a percentage of total development costs, and notes that, although an internal rate of return is a truer measure because it allows for time, the capital profit as a percentage of cost or value is what a basic appraisal usually shows.

// 02 — HOW IT IS CALCULATED

Total development cost = land + construction + contingency + fees + finance + sales costs
Profit = gross development value − total development cost
Profit on cost = profit ÷ total development cost
Profit on value = profit ÷ gross development value
On value = on cost ÷ (1 + on cost) On cost = on value ÷ (1 − on value)

Both sides need the same basis. Where GST applies to the sales, as it can on new homes in New Zealand and Australia, the sales value is taken net of it, and the costs on a matching basis; mixing the two inflates the margin. Finance belongs in the cost, which means the ratio moves with the interest rate and the length of the programme even when nothing on site changes.

// 03 — THE EXAMPLE

A mixed-use scheme of shops and apartments, constructed for this page like every figure in it, has a feasibility showing land US$5.5m, construction US$15.4m, contingency US$0.8m, fees US$1.6m, finance US$1.9m and sales costs US$0.8m, against sales of US$30.4m net of GST. The bank is asked for US$17.5m; the developer's equity is US$8.5m.

Total development cost 5.5 + 15.4 + 0.8 + 1.6 + 1.9 + 0.8 = 26.0
Profit 30.4 − 26.0 = 4.4
Profit on cost 4.4 ÷ 26.0 = 16.9%
Profit on value 4.4 ÷ 30.4 = 14.5%
Prices can fall 14.5% before the profit is gone,
then a further 8.5 of equity before the 17.5 loan: (30.4 − 17.5) ÷ 30.4 = 42%

The last line ignores the sales costs that would fall with the prices, and assumes everything has been spent. Now the lender reads the same scheme with its own inputs. Its valuer sets the sales values 4% below the feasibility's, its quantity surveyor adds US$0.6m to construction, and interest at the bank's own rate adds US$0.3m.

Sales value 30.4 × 0.96 = 29.18
Cost 26.0 + 0.6 + 0.3 = 26.9
Profit 29.18 − 26.9 = 2.28
Profit on cost 2.28 ÷ 26.9 = 8.5% (the feasibility showed 16.9%)

Nothing in the scheme changed between the two readings. Three moderate differences of opinion halved the cushion, which is why a lender recomputes the margin rather than accepting it, and why the inputs matter more than the ratio.

// 04 — THE MEASURES A LENDER READS BESIDE IT

Profit on cost is one sum read from the bottom. The same sum read for the land gives the residual land value: fix the profit and solve for what the site is worth. The loan is measured against the same two figures, by loan to cost and by loan to gross development value, which say where the bank sits beneath the margin and the equity.

Time is the measure the ratio leaves out. Two schemes at 16.9% on cost, one built and sold in eighteen months and one in thirty-six, are not equally safe: the longer one carries more interest, more exposure to a turn in the market, and more months in which costs can rise. A discounted cash flow and its internal rate of return show the difference, and a lender reading a long programme gives it weight.

DEFINED IN ONE PARAGRAPH → · RESIDUAL LAND VALUE, WORKED → · DEVELOPMENT FEASIBILITY →

// 05 — WHERE IT DECIDES A FILE

The margin decides how much bad news the file can take, and presales decide where that news can land. A presold unit's price is fixed, so the price cushion is carried by the unsold units alone. On a scheme half presold, their prices can fall about twice the headline percentage before the profit is gone, but only if every presale settles; a buyer who walks away puts a unit back into the market at the new, lower price. Issue 08 reads a townhouse feasibility that way: four of 24 homes presold, about 20% on cost as submitted, and about 12% if the unsold homes fall a further 8%.

There is no correct margin. A lender sets its own minimum for the risk in front of it, and a scheme below it is not refused by arithmetic alone: more equity, more presales or a fixed-price building contract can each make a thinner margin acceptable, and a developer with a record of overruns can make a thick one look thin.

PROPERTY DEVELOPMENT FINANCE → · ISSUE 08 · THE TOWNHOUSE FILE →

// SOURCES

The documents the statements on this page rest on. Each was opened and checked when cited.

  1. RICS, Valuation of development property, RICS professional standard, global, 1st edition (October 2019, effective 1 February 2020; reissued as a professional standard April 2023) — glossary 'Profit on cost' and 'Profit on value', and paragraph B2.2.3.2 — Defines profit on cost against total development costs (and profit on value against net development value), and says that although the IRR is a truer measure taking timing into account, a basic appraisal usually expresses profit as a percentage of total development cost including finance, or of GDV — sections 01 and 04.

// QUESTIONS PEOPLE ASK

What is a good profit on cost for a property development?
There is no single figure. The margin a developer needs, and a lender wants to see, depends on the size and length of the scheme, the presales or pre-lets already signed, the type of building contract and the state of the market. Each lender sets its own minimum for the risk. A margin is also only as good as its inputs: a high one built on optimistic prices protects less than a modest one built on presold contracts.
How do you convert profit on cost to profit on GDV?
Divide the profit on cost by one plus itself. A scheme at 25% on cost is at 0.25 ÷ 1.25, or 20%, on value. To go the other way, divide the profit on value by one minus itself: 15% on value is 0.15 ÷ 0.85, or about 17.6%, on cost. The profit is the same in both; only the base differs, and while there is a profit, the figure on value is the smaller of the two.
Is finance included in profit on cost?
Usually, yes. Total development cost normally includes interest and fees on the borrowing, which is why the ratio falls when rates rise or the programme lengthens. A lender checks which rate the feasibility assumed and for how long, and recomputes the interest on its own terms. An appraisal that leaves finance out shows a higher margin than the scheme will earn, and should say so.
What is the difference between profit on cost and return on equity?
Profit on cost divides the profit by the whole cost of the scheme; return on equity divides it by the developer's own money. In this page's example, US$4.4m of profit is 16.9% on a cost of US$26.0m but about 52% on equity of US$8.5m, because the bank funds the rest. The first is the lender's cushion; the second is the developer's reward for taking the first loss.

THE IN-TRAY · ONE MINUTE

Make the call on one file.

A short file on the ground this page covers. Every option opens with how far it sits from a senior banker’s read.

THE NUMBER · THE ECONOMY · COLLATERAL MARKETS

An office building earns US$1.0m a year of net operating income. Buyers price such buildings at a 5% yield, so it is valued at US$20m. The loan against it is US$12m.

If the yield buyers want rises to 6%, what is the loan-to-value?

1 FILES · PICK A CALL ON ANY OF THEM

3 MORE ON THE ECONOMY · COLLATERAL MARKETS →WHERE DO YOU READ FROM? THE PLACEMENT →