This 10-min calculation kills 80% of deals before wasting money on architects.
Here’s the formula:
Just saved a client $200K in design fees.
How?
10 minutes. A calculator. Brutal honesty.
Most developers get excited…
And immediately call the architect.
Wrong move.
Here’s the back-of-napkin formula that kills bad deals before they kill you:
Step 1: Land Value Check
→ Land price ÷ buildable square feet
Example:
$500K land ÷ 2,000 buildable sq ft = $250/sq ft land cost
→ If land is over 30% of total project cost per sq ft…
WALK!
Step 2: Construction Cost Reality
→ $300/sq ft minimum for basic construction
→ Add 10-12% for design, permits, engineering
→ Add 3-5% for overhead
Total build cost: ~$350/sq ft or easily over $500 for a downtown highrise.
→ Land + construction should be ≤ 80% of final sale or rental value.
Step 3: The 70-75% Financing Rule
→ Typical loan = 70-75% loan-to-cost
→ You cover the other 25-30% in cash
Quick math:
$1M project = $250K–$300K out of pocket
→ No cash? No deal.
Step 4: The 20% Profit Test
→ After all costs, demand 20% minimum profit
Why?
Because something always goes sideways.
Permits. Costs. Markets.
If it barely works on paper, it won’t work in real life.
Real Example:
Land: $500K
Buildable: 2,000 sq ft
Construction: $350 x 2,000 = $700K
Total cost: $1.2M
→ You need a sale price of $1.44M ($720/sq ft) to hit margin.
Can the market support $720/sq ft?
If not — walk away.
This math takes 10 minutes.
It saves you 6 months and $200K in soft costs.
I’ve seen developers spend $50K on plans for projects that never penciled — not even on Day 1.
Do the math first. Get excited later.
The deals that survive this test?
Those are the ones worth building.