Formula
GDV = units x (GIA per unit x NIA percent) x £ per sqft.
NIA is the saleable internal area. A new flat with 85 percent net-to-gross sells 850 sqft of every 1,000 sqft built.
When quick GDV is enough
- Land scouting before instructing a comparable report.
- Vendor conversations where you need a working number now.
- Pre-empt a brokerage pitch by checking their headline GDV.
When you need the full residual
- You are bidding on land tonight.
- Lender wants PoC and LTC.
- Sensitivity matters: a 10 percent GDV miss might still pencil, or might abort.
Inputs
MAX LAND BID£106,489At 20% profit on cost, 9 units, 950 sqft GIA each.
MARGINAL
GDV£3,088,688
Build cost£1,826,937
Prof fees£219,232
s106/CIL/BNG£108,000
Contingency£161,563
Finance interest£164,996
Target profit£496,146
Total costs (excl land)£2,480,729
Senior debt @ LTGDV£2,007,647
PoC19.4%
PoGDV16.2%
LTC77.6%
Sensitivity (PoC %)
Build -5%Build +5%Build +10%Build +15%Build +20%
GDV -15%11%1%-3%-7%-11%
GDV -10%18%7%2%-2%-6%
GDV -5%19%13%8%4%-1%
GDV 0%19%19%14%9%5%
GDV +5%18%19%19%14%10%
Cells show profit-on-cost percentage at each GDV stress / build-cost shock pair. Cells below your target PoC turn amber-warm; cells below 10 percent abort.