Most solo painters underprice their work by 20–30% — not because they're bad at painting, but because estimating is done in their head on the way to the front door. Here are the six things that separate a quote that holds from one that bleeds margin.

A paint estimate isn't just a price. It's the document that decides whether the job is profitable before you open a single can.

23%
average underpricing on solo contractor estimates in year one
faster to quote with a structured estimating system
$380
avg revenue lost per job from forgotten material costs

1 — Calculate square footage room by room — not as a whole house

The most common mistake is estimating the whole house as a single number. Walk each room individually and capture length, width, and ceiling height separately. This gives you scope control — if a customer wants to remove the master bedroom, you can reprice in seconds.

For each room, calculate paintable area based on which surfaces you're covering:

Surface area formulas
  • Walls2 × (L + W) × HAlmost always
  • CeilingL × WWhen painting ceiling
  • TrimPerimeter × 0.5 ftBaseboards & door casings
Example — 12×14 bedroom, 9ft ceilings, walls and ceiling
Walls — 2 × (12 + 14) × 9468 sqft
Ceiling — 12 × 14168 sqft
Total paintable area — this room alone636 sqft

Don't subtract for doors and windows. Paint saved is roughly offset by the extra cut-in work around them.

2 — Coat count depends on condition — don't default to two coats on every job

Square footage tells you area. Condition tells you how many times you'll cover it. This is where painters most often leave money on the table by quoting two coats regardless of what they're painting over.

Coat count by surface condition
  • Standard repaint2 topcoatsExisting paint in good condition
  • New drywall1 primer + 2 topcoatsBare drywall absorbs heavily
  • Dark or vivid colour3 topcoatsLight over dark, or vivid colours
Example

Customer wants bright white over existing navy walls. That's a dark-to-light change — price for 3 coats or you'll be applying that third coat for free.

3 — Calculate gallons using coverage rate — and always add a 10% waste buffer

Most interior latex covers 350–400 sqft per gallon per coat. The exact rate is on the label — use it, because it varies more than people expect between products.

The formula: (total coat-sqft ÷ coverage rate) × 1.10 — the 10% buffer accounts for cut-in waste, roller nap absorption, and the inevitable spill. Always round up to the nearest whole gallon.

Example — 1,200 sqft, 2 coats, 400 sqft/gal coverage
1,200 sqft × 2 coats2,400 coat-sqft
÷ 400 sqft/gal6 gallons
× 1.10 waste buffer6.6 → buy 7 gallons

Showing up mid-job for another can costs an hour and looks unprofessional. Round up — always.

Coverage rates by product tier
  • Premium (Aura, Duration)400 sqft/galDenser pigment, thicker body
  • Mid-range (SuperPaint, Regal)350–400 sqft/galMost common site use
  • Primer300–350 sqft/galBare surfaces absorb more

4 — Price materials with a markup — not at cost

A common mistake solo painters make is charging customers exactly what they paid at the store. Your time sourcing, driving to collect, and managing leftover stock has real value. A 15–25% material markup is standard and completely defensible.

What belongs in your materials line
  • Paint & primerYour actual cost per gallon × markup %
  • Tape & drop clothsEstimate per job, include in materials
  • Roller covers & brushesAmortise across jobs or charge per use
  • Sandpaper, spackling, caulkEstimate per job based on condition
Example — 20% materials markup
Materials at cost$320
20% markup applied+ $64
You charge the customer$384

That extra $64 covers sourcing time and gives you buffer if prices moved since you last checked.

5 — Split labor into prep time and paint time — they are not the same number

Labor is where estimates fall apart most often. The mistake is treating the whole job as one block of time. Prep and painting have different rhythms, and customers understand a breakdown far better than a lump-sum number.

Labor split — prep vs paint
  • Prep timeTaping, drop cloths, patching, priming spots, moving furnitureOften forgotten entirely
  • Paint timeCut-in, rolling, second coat, trimFlat sqft rate misses real pace
Example — 3-bedroom interior at $75/hr
Prep — 3 hrs × $75$225
Painting — 8 hrs × $75$600
Total labor — line by line$825

A number you can walk a customer through line by line — and it holds up to questions about why you charge what you charge.

Never let a tool guess your painting speed from square footage alone. You know your pace — own that number in the estimate.

6 — Put a validity date on every quote — and make the customer-facing version clean

Paint prices shift. A quote you write today based on current supplier pricing may not hold if the customer comes back six weeks later. Every quote should carry a 14–30 day validity window. When a quote expires and a customer returns, spend five minutes checking current costs before reissuing.

The estimate is your internal math. The quote is what the customer sees. These should feel different — the quote needs scope, line items, total, and validity. Three things customers ask when they push back on price:

How line-item quotes handle pushback
  • "Can you come down a bit?"I don't understand where this number comes fromThey can see materials vs labor vs markup — the number is defensible
  • "Can we skip the ceiling?"I want to reduce scope, not just the priceYou can instantly reprice by removing that line
  • "Another painter quoted less"Are they omitting something I should know about?Your breakdown shows exactly what's included
Pro tip

A secondary benefit of a validity date: it creates a natural nudge. Customers who are ready to commit tend to move. Those who are just gathering comparison quotes often don't — and those are not the jobs you want holding up your schedule.

A paint estimate isn't just a price. It's the document that decides whether the job is profitable before you open a single can.

— The CashWrench Team

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Room-by-room estimates with products, labor, and markup broken out. Know your number before you give it.