| Office Rent |
Fixed |
Include $2,500/month in monthly overhead before calculating required gross profit. |
Spreading rent across jobs and making break-even look lower in slow months. |
| Business Insurance |
Fixed |
Include $1,200/month as a recurring overhead charge from Month 1 through Month 60. |
Treating policy payments as job-only expense when the bill continues without new work. |
| Installation Materials & Supplies |
Variable |
Deduct 12.0% of first-year revenue as a direct job expense in contribution margin. |
Using gross revenue as contribution and ignoring supplies tied to each installation. |
| Vehicle Fuel & Transportation |
Variable |
Deduct 8.0% of first-year revenue because travel rises with jobs, site visits, and crews. |
Putting all vehicle spend in fixed overhead and overstating job margin. |
| Project Insurance & Permits |
Variable |
Deduct 4.0% of first-year revenue when estimating job-level contribution. |
Forgetting permits and project coverage, then setting prices too close to labor rates. |
| Tool & Equipment Maintenance |
Semi-variable |
Model 3.0% of first-year revenue, but review monthly for a base repair reserve. |
Treating maintenance as zero until tools fail, then blaming one bad month. |
| Installer Salaries |
Semi-fixed |
Step payroll up as full-time equivalents increase, not with each single job sold. |
Treating salaried installers like pure job labor when payroll still hits during slow weeks. |
| Marketing Budget |
Semi-fixed |
Use the planned annual budget, starting at $24,000 in the first year, as a capacity-building spend. |
Calling marketing fully variable even though campaigns often run before booked revenue arrives. |