| Lab Facility Rent |
Fixed |
Use $15,000 per month as base overhead in the monthly break-even model. |
Allocating rent per tissue and assuming it falls as volume rises. |
| Laboratory Insurance |
Fixed |
Hold at $1,800 per month unless the policy changes. |
Making insurance move with each order or revenue dollar. |
| Administrative Overhead |
Fixed |
Include intellectual property maintenance, general administrative, software subscriptions, and security and cleaning as stable monthly overhead. |
Dropping small fixed items because each line looks immaterial. |
| Utilities and Internet with Cleanroom Utilities Share |
Semi-variable |
Model the $2,500 monthly base plus the 0.1% revenue-linked cleanroom utilities share by product. |
Treating all utilities as fixed and missing usage tied to cleanroom output. |
| Regulatory Compliance and QA |
Semi-fixed |
Start with the $3,000 monthly base, then add capacity steps as QA workload and staffing rise. |
Modeling compliance as a simple percentage of revenue. |
| Payroll by FTE |
Semi-fixed |
Use forecasted salary steps, from $490,000 in the first year to $1.28 million in Year 5. |
Tying the whole team to sales instead of planned staffing levels. |
| Direct Unit Production Inputs |
Variable |
Apply per-unit inputs for purified cells, growth factors, bio-ink materials, direct lab labor, sterilization, and packaging. |
Treating consumables or utilization-linked direct lab labor as fully fixed. |
| Revenue-Linked Fees and Allocations |
Variable |
Apply sales commissions, regulatory submission fees, QC batch testing, biohazard waste, and equipment maintenance allocation as revenue-linked items. |
Treating maintenance allocation as fully fixed when the model links it to revenue. |