Start free. Add expert input only when it earns its keep.
Four packages, in order of depth. Most people start with the free sprint and stop when they have enough. Everything upstream of manufacturing is fixed-fee – no scope surprises.
Four packages. Start free. Go deeper only when it earns its keep.
PACKAGES · FIXED FEEFree Sprint
A fast, AI-guided interview through stages 01–05. Produces a quick-draft Specification and Viability Report, copy-ready to refine before you brief an engineer. Full mechanism on the Viability Sprint page.
- Structured step-by-step interview
- Viability: strengths, risks, next step
- Market potential & challenges
- Must-have vs nice-to-have features
- Timeline and cost bands
- Copy-ready Specification & Viability Report
Engineer-Verified Review
A working engineer reviews your sprint output, sharpens the numbers, flags what AI missed, and gives you a clear viability assessment.
- Everything in Free Sprint, plus
- 30-minute engineer video review
- Refined cost estimates (supplier-informed)
- Risk flags AI may have missed
- Manufacturing method recommendation
- Written summary within 48 hours
Expanded Specification
Your sprint and review output transformed into a professional, branded specification document – ready for investors, manufacturers, or engineering teams.
- Everything in Engineer Review, plus
- Branded Product Specification (.docx)
- Prioritised requirements summary
- Design Brief document
- Investor / funder-ready formatting
- Engineer-ready formatting
Handover-Ready Package
A dedicated handover session with a custom development roadmap, manufacturing strategy, and direct introduction to the engineering team.
- Everything in Expanded Spec, plus
- 1-hour specialist consultation (video)
- Custom development roadmap
- Manufacturing strategy & method selection
- Supply chain considerations
- Direct Cast Iron CAD team introduction
- Priority engineering quotation
ALL PRICES INC. VAT · NO SCOPE SURPRISES · FIXED FEE UPSTREAM OF MANUFACTURE
– NOTE · All IEN tiers produce validated documents. Physical engineering work (CAD, prototyping, tooling, manufacturing) is delivered separately by Cast Iron CAD, quoted per project.
What’s included at each level.
FEATURE MATRIXEvery tier builds on the one before. You never pay for something you’ve already received.
Which tier do you need?
GUIDE · TIER MATCHMost people start with the Free Sprint. That’s the point – it’s free because it’s where most ideas either prove themselves or get quietly retired.
Add the Engineer-Verified Review (£129) if you want a human to sanity-check what came out. Add the Expanded Specification (£399) if you need a document you can hand to someone else. Take the Handover-Ready Package (£699) if you’re serious about moving into prototyping and want a direct route into Cast Iron CAD.
Stages 6–10 – design, develop, engineer, manufacture, deliver – are quoted project-by-project through Cast Iron CAD once the spec is solid.
The methodology behind the price tags.
PROOF · CAST IRON CAD LINEAGEThe paid tiers aren’t a separate product – they’re the same methodology Cast Iron CAD has used on 280+ projects across 15 years, applied to your sprint output. The Free Sprint is that methodology captured in an AI-guided interview; the paid tiers add the working engineer back into the loop.
Questions before you pick a tier.
FAQ · SIX COMMON ONESDo I have to?
No. Running the Free Sprint and walking away is a supported outcome. The paid tiers exist for people who want a human to verify the output before they commit real money – not as a required upgrade.
Fixed fee?
Yes, at every tier up to and including Handover. Scope is defined up front. Physical engineering (CAD, prototyping, tooling, manufacturing) is quoted separately by Cast Iron CAD once the spec is locked.
Skip tiers?
Yes. If you’ve already completed the sprint and know you want the Expanded Spec, you can buy it directly – the Engineer Review is bundled into it. Same logic applies at Handover.
Lead time?
Engineer Review: written summary within 48 hours of the video call. Expanded Spec: 5 working days. Handover: scheduled within 2 weeks, deliverables inside 10 working days.
IP & NDA?
Your Free Sprint session is private by default. If the Viability Report flags qualifying IP and you want to proceed to paid review, we put an NDA in place before the review starts.
Refund?
Engineer Review: refundable until the call is scheduled. Expanded Spec & Handover: refundable until work begins. Once deliverables are drafted, partial refund proportional to the stage reached.
Every tier starts with the same free sprint.
Whether you end up at £0 or £699, the first hour is identical. Run the sprint, read the Viability Report, then decide whether a human should verify it. The ladder exists so you can climb as far as the evidence says you should – and stop when it doesn’t.