Builder vs Broker ROI Calculator

The Math Behind the Calculator

The calculator runs two parallel scenarios on your project specifics and reports the net proceeds delta. The inputs that drive the comparison are days on market (DOM), carry cost per unit per month, marketing spend, commission rate, and price lift from MLS exposure.

Builder-led scenario. Net = (List Price - Cost Basis - Marketing Budget - (Carry x Builder DOM / 30)) x Units. The builder keeps 100% of the closed price minus their costs and saved commission, but pays full carry cost during the longer DOM and absorbs marketing expenses directly.

Broker-listed scenario. Net = (List Price x (1 + Price Lift) - Cost Basis - (List Price x Commission Rate) - (Carry x Broker DOM / 30)) x Units. The builder pays commission on the higher closed price but eliminates marketing budget (broker covers it), captures the price lift, and reduces carry by the DOM delta.

What flips the comparison? The break-even point depends on how aggressive the price lift assumption is and how high carry cost runs. On a $4,200/month carry per unit at the Q1 2026 Austin DOM medians (96 vs 73 days), the broker scenario typically wins on net even before the price lift kicks in. On lower-carry, lower-priced suburban product, the comparison narrows. The calculator lets you stress-test your specific project rather than relying on a generic rule of thumb.

Conservative inputs. The defaults are set conservatively. The 2% price lift assumption is below the 3-5% typical, the 73-day broker DOM is the Q1 2026 median (some submarkets run faster), and the $12K builder marketing budget per unit reflects what builders actually spend, not what they think they spend. Higher accuracy comes from plugging in your actual cost basis, your actual carry rate, and your honest DOM history on prior projects.

Inputs the Calculator Does Not Model

• Builder time cost. Self-marketing consumes builder hours on listing inquiries, showings, qualifying buyers, contract review. The calculator does not assign a $/hour cost to builder time. Realistic estimate: 8-12 hours per unit during active marketing window. At builder hourly opportunity cost (typically $200+/hour at the boutique scale), that is $1,600-$2,400 per unit not captured in the math.
• Buyer-pool quality. MLS-listed product reaches the full buyer-agent network. Builder-marketed product often misses 60%+ of qualified buyers represented by exclusive buyer agents. The price lift assumption is the proxy for this effect, but in tight markets the access advantage compounds beyond price into transaction certainty.
• Closing certainty. Builder-marketed contracts have higher fall-out rates because the buyer pool skews toward unrepresented buyers with less due diligence support. Each fall-out adds 30-60 DOM to the actual close timeline. The calculator uses median DOM but real-world variance is higher for self-marketed product.
• Construction loan covenant pressure. Lenders typically require sales pace milestones during the construction loan term. Falling behind triggers covenant pressure and can force price drops. Broker partnerships with predictable MLS launch timelines reduce this risk - not modeled in the calculator but real on every project.
• Repeat business and reputation. Building a track record of fast-absorbing projects with broker partnerships compounds across the next project, the next capital partner, and the next land acquisition opportunity. Self-marketed slow projects compound the opposite direction.

The point of the calculator is to anchor the comparison in numbers rather than vibes. The numbers say broker-listed wins on most Austin builder math at current Q1 2026 inputs. The numbers do not capture the strategic value of a repeat partnership. Both matter.