Status
Conditional / post-MVP. Do not start unless the MVP is validated and there is signal that users want a "total cost of build (car + parts)" view. Parking this so we don't lose the research.
Problem
Users associate a car (year/make/model/trim, optionally VIN) with a build list and track the cost of parts they add. Today there's no way to see the total cost of the build including the base car — only the parts side. A common question from enthusiasts is "what did this build cost end-to-end," and the base vehicle is usually the largest single line item.
Proposed feature
When a user associates a car with a build list, optionally fetch a fair-market valuation for that vehicle and display:
- Estimated base car value (range + point estimate)
- Total build cost = base car estimate + sum of parts on the build list
- Last-updated timestamp on the valuation
- Disclaimer that the value is an estimate, not an appraisal
User-facing entry point: a button/section on the build list page like "Estimate base car cost" that triggers the lookup. Cached aggressively per car.
Data source research
Kelley Blue Book has no self-serve public API — valuations are licensed through Cox Automotive under enterprise contracts (dealer/OEM/lender). Not viable for an indie product.
Two realistic third-party options:
MarketCheck (preferred)
- Transparent, published pricing
- Subscription tiers: Free (500 calls/mo), Basic $299/mo (5k cap), Standard $749/mo (unlimited)
- Per-call valuation rates:
- MarketCheck Price US Used Base — $0.07/call ($70/1k)
- Premium — $0.09/call ($90/1k)
- Premium Plus — $0.13/call ($130/1k)
- Basic VIN decoder is $0.0015/call ($1.50/1k) — useful for a cheap "decode VIN → year/make/model/trim" step before deciding whether to spend on a valuation
- Docs: https://docs.marketcheck.com/docs
- Pricing: https://www.marketcheck.com/apis/pricing/
Vehicle Databases (fallback)
- No published per-call pricing; gated behind "book a demo" / free trial (15 credits)
- Available on RapidAPI under standard Basic/Pro/Ultra/Mega tiers (~$25–$150/mo) — would need to inspect the listing to confirm quotas
- Worth evaluating only if MarketCheck accuracy is insufficient or we need their license-plate-to-VIN endpoint
- https://vehicledatabases.com/vehicle-market-value-api
Free/cheap fallbacks (no pricing)
- NHTSA vPIC API — free, decodes VIN to year/make/model/trim only, no pricing data
- Could be combined with a static depreciation curve as a zero-cost "rough estimate" tier for free users
Cost control strategy
At $0.07–$0.13 per valuation, naive per-page-view lookups would be expensive at scale. Required mitigations before shipping:
- Cache valuations per car for 30–90 days. A single valuation should serve thousands of page views of that build list.
- Gate behind paid subscription tiers, or surface as a one-time "refresh estimate" action rather than auto-fetching.
- Two-tier offering: free users get an NHTSA-decode + static depreciation estimate; paid users get the live MarketCheck valuation.
- Track API spend per user / per month for early signal on abuse or unexpected cost.
Open questions (defer until we revisit)
- Is total-build-cost a feature users actually ask for, or just one we assume they want? (Validate via MVP feedback before building.)
- Free tier vs. paid-only — does the rough estimate cheapen the paid valuation, or does it act as an upsell?
- Do we expose the raw price range from MarketCheck, or smooth/round it to avoid implying false precision?
- VIN entry — optional or required? VIN gives a much tighter estimate but adds friction.
Acceptance criteria (when/if we pick this up)
References
Status
Conditional / post-MVP. Do not start unless the MVP is validated and there is signal that users want a "total cost of build (car + parts)" view. Parking this so we don't lose the research.
Problem
Users associate a car (year/make/model/trim, optionally VIN) with a build list and track the cost of parts they add. Today there's no way to see the total cost of the build including the base car — only the parts side. A common question from enthusiasts is "what did this build cost end-to-end," and the base vehicle is usually the largest single line item.
Proposed feature
When a user associates a car with a build list, optionally fetch a fair-market valuation for that vehicle and display:
User-facing entry point: a button/section on the build list page like "Estimate base car cost" that triggers the lookup. Cached aggressively per car.
Data source research
Kelley Blue Book has no self-serve public API — valuations are licensed through Cox Automotive under enterprise contracts (dealer/OEM/lender). Not viable for an indie product.
Two realistic third-party options:
MarketCheck (preferred)
Vehicle Databases (fallback)
Free/cheap fallbacks (no pricing)
Cost control strategy
At $0.07–$0.13 per valuation, naive per-page-view lookups would be expensive at scale. Required mitigations before shipping:
Open questions (defer until we revisit)
Acceptance criteria (when/if we pick this up)
References