| Commercial rent |
Fixed |
Include $5,000 per month in fixed overhead from Month 1 through Month 60. |
Reducing rent in slow months instead of treating it as lease-driven capacity. |
| Store insurance |
Fixed |
Include $300 per month as fixed overhead across the full model period. |
Modeling insurance as a percentage of sales. |
| Website hosting, point-of-sale, and customer management subscriptions |
Fixed |
Include $300 per month: $50 hosting, $150 point-of-sale, and $100 customer management software. |
Omitting small recurring tools because each line looks immaterial. |
| Store staffing payroll |
Fixed |
Use $152,500 per year, or about $12,708 per month, in the first operating year unless hours flex with traffic. |
Treating salaries as variable without changing schedules. |
| Product inventory cost |
Variable |
Apply 12.0% of sales in the first operating year, improving to 10.0% in the mature year. |
Loading the $30,000 opening inventory buy into monthly break-even instead of runway. |
| Inbound shipping and handling |
Variable |
Apply 2.0% of sales in the first operating year, declining to 1.5% in the mature year. |
Counting freight twice inside both inventory and variable expenses. |
| Payment processing fees and sales commissions |
Variable |
Apply 5.5% of sales in the first operating year: 2.5% processing plus 3.0% commissions. |
Using gross margin before card fees and commissions. |
| Utilities and store maintenance |
Semi-variable |
Start with $800 utilities and $400 maintenance per month, then increase only when hours or traffic justify it. |
Locking them forever at $1,200 despite longer store hours. |