About this site
About The Cost Sheet
Published by Cydney Mar Last updated: November 2026
The Cost Sheet is published by Cydney Mar, a product development strategist who helps founders turn product ideas into real, scalable businesses.
Cydney Mar publishes The Cost Sheet as a free tools and templates resource on product costs and margins for consumer products sold through retail, TV and direct to consumer channels. It is one of a small number of websites Cydney Mar publishes; the main business website is cydneymar.com.
Who publishes The Cost Sheet?
Cydney Mar publishes this site, writes its tools and checklists, and stands behind them. She is a product development strategist with 45+ years in fashion and product and $300M+ in global retail, TV and DTC sales, as stated on cydneymar.com. For 15+ years she sold her own collections on QVC in 8 countries, with more than 800 hours of live television.
Her product work has spanned fashion, jewelry, bath bombs, scented candles, homewares, paper products, car accessories and her own Cydney Mar Wellness vitamins and supplements. She designed Cirque du Soleil's first Boutique Collection and led design for Edwin Jeans in North America. She is based in Montreal and runs Cydney Mar Consulting, an Indigenous-owned product development firm.
- years in fashion and product
- 45+
- in global retail, TV and DTC sales
- $300M+
- hours of live TV
- 800+
- countries on air
- 8
Why this site exists
Costs and margins decide whether a product works
Many founders take the right steps in the wrong order: sampling without clarity, picking suppliers on guesswork, and ignoring margins until it is too late. The Cost Sheet puts the costing tools in one place so founders can check their numbers early, before money is committed to production.
Part of the Concept-to-Reality Pathway
Cost and Margins is one of six stages in Cydney Mar's Concept-to-Reality Pathway: Product Clarity, Right Prototypes, The Right Suppliers, Cost and Margins, Production-Ready, and Launch and Scale. Founders who want guidance on the whole path, or a second opinion on their numbers, can contact Cydney Mar. Prices for her services are not listed on this site.
Is The Cost Sheet independent?
No. The Cost Sheet is published by Cydney Mar, who offers product development services, and the site invites readers to contact her. The tools are free to use with no sign up. Outside figures are credited to their published sources, and how every tool works is explained on the methodology page. Start with the product costing calculator.
Common questions
See all 48 questions in the FAQWhat experience does Cydney Mar have?
Cydney Mar has 45+ years in fashion and product and over $300 million in retail, TV and DTC sales. She sold her own collections on QVC for 15+ years in 8 countries, designed Cirque du Soleil's first Boutique Collection and led design for Edwin Jeans in North America.
What does a consumer product development consultant do?
A consumer product development consultant guides founders from idea to a product ready to sell. Cydney Mar's Concept-to-Reality Pathway covers six stages: product clarity, the right prototypes, the right suppliers, costs and margins, production readiness, and launch and scale through retail, DTC or TV.
What is a product development strategy?
A product development strategy is the order of decisions that takes an idea to a product people buy: who it is for, what it is, how it is sampled, who makes it, what it costs and how it reaches market. Cydney Mar's approach centers on doing the right steps in the right order, which reduces costly guesswork.
How do product development consulting firms work with founders?
Product development consulting firms usually work through strategy sessions, defined programs or ongoing advisory. Cydney Mar runs Cydney Mar Consulting, an Indigenous-owned product development firm based in Montreal, and starts with a strategy call to talk through your idea. Prices are not published, so contact her directly for current options.
Can a product manufacturing consultant help with suppliers?
Yes. Finding the right suppliers is one of the six stages of Cydney Mar's Concept-to-Reality Pathway, which looks for suppliers vetted for quality, communication and reliability. Her work also covers sampling, sourcing, costing and production readiness, so suppliers are chosen with real costs and margins in mind.
What is a tech pack for a garment?
A garment tech pack is the technical document a factory uses to make your product: specifications, measurements, materials and construction details. Cydney Mar describes a clear, professional tech pack as the difference between a sample that is right the first time and months of expensive back and forth with a factory.
Want an expert on your numbers before you commit?
Cost and Margins is one stage of Cydney Mar's Concept-to-Reality Pathway, which takes founders from product clarity to prototypes, suppliers, production readiness and launch in retail, TV or DTC.