Lapidary Supply Store Break-Even Analysis: $257K Monthly Sales

Fixed costs $19.1K/mo Base burn

Contribution margin 81% After variable costs

Break-even revenue $23.6K/mo Cover burn

Break-even timing Month 25 Model crossover

Break-even calculator

Use this calculator to test whether monthly revenue clears variable costs and the fixed cost base.

Lean Base Full

Monthly revenue Revenue sets the cash left after direct costs to cover rent, wages, and overhead. $ Low sales High sales Variable expenses Use direct costs that rise with sales, like product buying, logistics, and payment fees. $ Lean costs Heavy costs

Money available to cover fixed costs $28,500 $35,000 revenue - $6,500 variable expenses

Margin ratio

81%

Covers fixed costs

Yes

Fixed monthly costs This is the monthly cost base the store must cover before profit starts. $ Lower base Higher base

Break-even chart Revenue Total costs

Which expenses stay fixed, and which move with sales in a lapidary supply store?

Cost classification

Break-even gets unreliable when one-time inventory, card fees, and payroll are lumped together. Here, fixed monthly overhead starts with rent and core payroll, while revenue-linked costs should scale with sales.

Expense	Cost	Break-Even Treatment	Common Mistake
Retail Showroom Rent	Fixed	Use $4,200/month from Month 1 through Month 60.	Tying rent to sales volume instead of treating it as baseline overhead.
Utilities and Security	Semi-fixed	Start with the $750/month base, then review capacity needs as shop traffic rises.	Ignoring higher shop load during busier periods.
Product Acquisition and Logistics	Variable	Apply 14.0% of first-year revenue, declining to 12.0% by the fifth year.	Treating initial inventory stocking as monthly overhead.
Payment Processing and Fulfillment	Variable	Apply 5.0% of first-year revenue, declining to 4.0% by the fifth year.	Burying card and fulfillment fees inside gross margin.
General Manager payroll	Fixed	Use $6,000/month for 1.0 full-time equivalent across all five years.	Excluding owner-level or manager labor from break-even overhead.
Sales and Workshop Assistant	Semi-variable	Use $1,750/month in the first year based on 0.5 full-time equivalent.	Adding staff before visitor traffic and workshop demand support it.

How does break-even shift from a lean launch to a full lapidary supply store setup?

Scenario table

Break-even moves fast because fixed payroll and store costs rise faster than sales in the first two cases. By Year 3, revenue clears the heavier cost base and the model finally shows a cushion.

Planning cases only; actual break-even will move with traffic, product mix, and staffing pace.

Scenario	Monthly Revenue	Variable Costs	Fixed Costs	CM Ratio	Operating Profit	Break-Even Signal
Lean launch case	$6.3K	$1.2K	$22.7K	81%	$-17.6K	Well below break-even; sales do not cover the first-year cost base.
Base Year 2 ramp	$31.6K	$5.8K	$30.1K	81.7%	$-4.3K	Near break-even, but the model still runs a small loss.
Full Year 3 scale	$63.9K	$11.2K	$33.5K	82.5%	$19.3K	Above break-even with a clear operating cushion.

What breaks the lapidary supply store’s break-even plan?

Stress test

Launch break-even is about $257K a month, and there’s no cushion at that line. A 20% revenue miss, a 10% fixed-cost bump, or weaker margins each push the hurdle higher fast.

Stress Case	Changed Assumption	Break-Even Revenue	Revenue Gap	Risk Signal
Current plan	No change.	$257K/month	$0 gap	No cushion at launch.
Revenue shortfall	Sales land 20% below break-even.	$257K/month	$51K gap	That miss leaves about $42K of monthly contribution to replace.
Fixed-cost increase	Fixed costs rise 10%.	$267K/month	$10K gap	Payroll, rent, or overhead creep can erase the cushion.
Margin pressure	Variable expenses rise and cut margin.	$283K/month	$26K gap	Discounting and freight push the sales bar fast.
Combined pressure	Revenue softens while fixed and variable costs both rise.	$294K/month	$37K gap	Stacked pressure makes Month 25 break-even harder to hold.

Can this lapidary supply store survive the ramp before you sign the lease and buy the first inventory load?

Founder checklist

This store is only ready for a lease and first buy if weekday traffic holds in the 42-to-110 range, conversion stays at 2.5%, and the business can survive the $391K cash trough in Month 25. If any of those slip, slow the lease, inventory, and hiring decisions.

1Traffic proof42-110/day

Confirm weekday foot traffic really lands in the 42-to-110 range before you lock the lease, because the store only works if that demand is real.

2Buyer rate2.5%

Keep the visitor-to-buyer rate honest before big ad spend, since weak conversion means you need more traffic, not a bigger budget.

3Fixed load$8.5K/mo

The non-payroll fixed load is about $8.5K a month, so make sure rent, utilities, marketing, platform, insurance, and supplies can sit under that line.

4Margin check81% CM

Product acquisition and logistics at 14% plus payment processing and fulfillment at 5% leave about 81% contribution margin, which is the cash left for wages and overhead.

5Launch capex$243.5K

Keep the $120K opening inventory separate from the $243.5K launch capex, or you’ll blur startup spend with operating break-even.

6Cash runwayMonth 25

Protect the $391K cash trough through Month 25, keep the opening team lean, test shipping workflow before scaling online sales, and add the e-commerce coordinator only when repeat orders can support the salary.