| Property lease |
Fixed |
Put $25,000 per month into the overhead base before booth rent and sales commissions are tested. |
Treating lease as if it falls when vendor sales are slow. |
| Payroll |
Semi-fixed |
Use $265,000 per year, or about $22.1K per month, in the first-year overhead base; step up when sales associate staffing rises. |
Scaling every payroll dollar with sales instead of modeling staffing steps. |
| Utilities |
Semi-variable |
Start with the $3,000 monthly base, then stress-test higher usage when traffic, shared checkout volume, and events rise. |
Calling utilities fully fixed even when longer hours and busy weekends lift usage. |
| Property insurance |
Fixed |
Load $1,500 per month into fixed overhead for the relevant planning range. |
Flexing insurance with booth rent or sales commissions. |
| POS system and software |
Fixed |
Put the $500 monthly software charge in fixed overhead; keep card fees separate in the variable ratio. |
Blending software fees with payment processing and hiding the true sales drag. |
| Security services |
Semi-fixed |
Use the $1,200 monthly base, then add a step if events, vendor count, or operating hours expand. |
Leaving security flat while shared space risk and event traffic increase. |
| Professional services and general maintenance |
Fixed |
Include the combined $1,800 per month in fixed overhead for routine accounting, advisory, repairs, and upkeep. |
Forgetting small shared-space overhead that still must be covered by booth rent. |
| Payment processing fees, marketing and advertising, event production costs, and consignment service costs |
Variable |
Add these to the first-year variable ratio: 4.0% processing, 8.0% marketing, 1.0% events, and 0.5% consignment service. |
Treating marketing and event costs as fixed even when traffic and vendor activity rise. |