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Methodology

How Calculations Work

From raw assumptions to investment-ready metrics — here's the logic behind every number in Profivo.

Revenue Logic

Revenue in a development appraisal starts with Gross Development Value (GDV) — the total expected sales proceeds from all units in the project. Profivo calculates this by summing each unit type's contribution: quantity multiplied by area multiplied by the price per square meter.

From GDV, sales costs are deducted: agent commissions (as a percentage of GDV), legal fees for conveyancing, and any additional selling costs you define. VAT handling is configurable — prices can be entered inclusive or exclusive of VAT, and the engine adjusts accordingly.

The result is Net Development Value (NDV), which represents the actual revenue available to cover costs and generate profit.

// Gross Development Value
GDV = Sum( quantity × area_m2 × price_per_m2 ) for each unit type

// Sales Costs
Sales Costs = (agent_fee% + legal_fee% + extra_fee%) × GDV

// Net Development Value
NDV = GDV - Sales Costs - VAT adjustment

In practice: A 1% change in price/m² on a project with 50 units at 70 m² each can shift GDV by tens of thousands. Revenue assumptions are the single biggest lever in any appraisal.

Cost Logic

Build costs form the foundation of the cost structure. Profivo calculates them as a rate per square meter of Gross Internal Area (GIA), multiplied by the total GIA. For phased projects, costs can be split across construction phases with different rates.

On top of direct build costs, the engine layers contingency (a percentage buffer for unknowns), preliminary costs (fixed setup amounts for site establishment, temporary works, and professional fees), and other costs which can be defined as a percentage of build cost, a percentage of GDV, or a fixed amount.

// Direct Build Costs
Build = cost_per_m2 × total_GIA per phase

// Contingency
Contingency = contingency% × Build

// Total Build
Total Build = Build + Contingency + Preliminaries + Other Costs
  • Other costs based on % of build — scales with construction complexity
  • Other costs based on % of GDV — scales with project value (e.g., marketing)
  • Other costs as fixed amounts — known quantities like planning fees

In practice: Build costs are typically the largest single expense in a development, often 40-60% of total project costs. Getting this right is critical to an accurate appraisal.

Finance Logic

Development finance typically involves two layers. Senior debt is the primary facility — defined by facility amount, annual interest rate, arrangement fee (charged upfront as a percentage of the facility), and exit fee (charged on repayment). Mezzanine debt is a secondary, higher-cost layer that fills the gap between senior debt and equity.

Interest is calculated monthly on the drawn balance. As costs are incurred each month, the drawn amount increases, and interest accrues on the cumulative balance. This compounding effect means that timing of expenditure directly impacts total finance costs.

Equity is the residual — whatever total project costs (excluding finance charges) are not covered by debt. Loan-to-Value (LTV) measures debt against GDV, while Loan-to-Cost (LTC) measures debt against total costs.

// Monthly Interest Accrual
Monthly Interest = drawn_balance × (annual_rate / 12)

// Total Finance Costs
Total Finance = Sum(monthly_interest) + arrangement_fee + exit_fee

// Equity Requirement
Equity = Total Costs (excl. finance) - Total Debt Facilities

// Key Ratios
LTV = Total Debt / GDV   |   LTC = Total Debt / Total Costs

In practice: Finance costs on a 24-month project at 8% with a 65% LTC can easily reach 5-10% of total project value. Ignoring the compounding effect of monthly accrual underestimates costs significantly.

Cash Flow Logic

A development appraisal is fundamentally a cash flow model. Profivo spreads all costs and revenues across a monthly timeline using S-curve distribution — a realistic pattern where spending starts slowly, peaks in the middle of a period, and tapers off toward the end.

Land acquisition cost is typically placed in month 1 as a lump sum. Build costs are spread across the defined construction period using the S-curve. Revenue from sales is spread across the sales period, usually starting after construction begins or completes, depending on the market.

Escalation can be applied to both costs and revenues — an annual percentage increase that is compounded monthly. This models inflation or expected market movement over the project timeline.

// S-Curve Distribution
Monthly Allocation = total_amount × s_curve_weight[month]

// Escalation (annual rate applied monthly)
Escalated Value = base_value × (1 + annual_rate/12)^month

// Cumulative Cash Flow
Net Position[m] = Sum(revenue[1..m]) - Sum(costs[1..m])

In practice: Same profit, different timing = different IRR. A project that generates all revenue in month 24 will have a lower IRR than one with phased sales starting in month 12, even if total profit is identical.

Profitability Logic

Profivo calculates a full suite of profitability metrics. Each one tells a different part of the story — absolute return, efficiency, time-adjusted performance, and investor returns.

Profit is the straightforward difference between NDV and total costs. Margin expresses this as a percentage of revenue. Return on Cost (RoC) expresses profit relative to total expenditure — this is the developer's primary metric because it measures how efficiently capital is deployed.

IRR (Internal Rate of Return) is the annualized return derived from the monthly cash flow profile, solved iteratively using the Newton-Raphson method. NPV discounts all future cash flows to present value at a chosen rate. MOIC (Multiple on Invested Capital) shows total equity returned divided by equity invested — a simple but powerful measure for equity investors.

// Core Profitability
Profit = NDV - (Land + Build + Other + Finance)
Margin = Profit / NDV
RoC = Profit / Total Costs

// Time-Adjusted Returns
IRR = rate where NPV(cash_flows) = 0 // Newton-Raphson solver
NPV = Sum( cash_flow[m] / (1 + discount_rate/12)^m )

// Investor Metric
MOIC = Total Equity Returned / Equity Invested

In practice: A project with 20% RoC but negative IRR has a timing problem — the profit is there, but it takes too long to realize. Always examine RoC and IRR together to get the full picture.

Scenario Logic

Every project faces uncertainty. Profivo models three scenarios — Base, Upside (optimistic), and Downside (pessimistic) — to bracket the range of possible outcomes.

Each scenario applies percentage deltas to five key variables: GDV (revenue), build costs, land costs, other costs, and interest rates. The engine then recalculates all metrics for each scenario independently, giving you a complete appraisal under each set of assumptions.

For example, the downside scenario might model GDV falling 10% while build costs rise 5%. The upside might model GDV rising 5% with costs unchanged. The base case uses your inputs as entered.

// Scenario Adjustments
Scenario GDV = Base GDV × (1 + gdv_delta%)
Scenario Build = Base Build × (1 + build_delta%)
Scenario Land = Base Land × (1 + land_delta%)
Scenario Other = Base Other × (1 + other_delta%)
Scenario Rate = Base Rate + rate_delta

// All metrics recalculated per scenario
Scenario Profit, RoC, IRR, MOIC ... independently derived

In practice: If the downside scenario still shows 10%+ Return on Cost, the project is resilient. If it turns negative, you need to understand exactly which variable drives the loss before proceeding.

Sensitivity Logic

Sensitivity analysis goes beyond scenarios by testing every combination of two variables simultaneously. You choose any two of five input variables, and Profivo generates a matrix showing how RoC and Profit change across the full range.

Each axis steps from -20% to +20% in 5% increments, creating a 9×9 heatmap of 81 possible outcomes. The center cell represents your base case. Cells are color-coded: green indicates profitable outcomes, transitioning through yellow to red for loss-making combinations.

This reveals which variables have the most impact. If the entire column changes color when you adjust GDV, but rows barely shift when build cost moves, you know that revenue risk dominates your project.

// Sensitivity Matrix
Variable A = [-20%, -15%, -10%, -5%, 0%, +5%, +10%, +15%, +20%]
Variable B = [-20%, -15%, -10%, -5%, 0%, +5%, +10%, +15%, +20%]

// For each combination (81 cells):
Cell[i,j] = recalculate( base + delta_A[i], base + delta_B[j] )
// Output: RoC and Profit for each cell
// Color: green (profitable) → yellow (marginal) → red (loss)

In practice: Sensitivity analysis shows which variable has the most impact on your returns. If most of the heatmap stays green even at -15% on both axes, you have a robust project with significant headroom.

See these calculations in action.

Build a full appraisal in 15 minutes and watch every metric recalculate in real time.