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Resale Value
What's it actually worth used? Depreciation curves, condition grading, and comparables math
Unify Dynamics LLC
Tools10read-only
Sign-inNoneno account, no key
Data keptNoneprocessed in memory
PriceFreeoptional Pro limits
StatusLiveMCP + REST
Works withMCP · RESTany agent
Try asking
Real questions, and the tools your agent calls to answer them.
My 3-year-old laptop cost $1200 new and is in good condition — roughly what's it worth used?
Tools called
estimate_depreciationHow fast do electronics lose value compared to furniture?
Tools called
category_depreciation_curveHow do I grade the condition of a used jacket I'm selling?
Tools called
condition_gradingWhat's the condition multiplier for 'fair' condition sporting goods?
Tools called
price_multiplier_for_conditionWhat should I do before listing my old phone for sale?
Tools called
resale_readiness_checklistWhere should I sell this — general platform tradeoffs?
Tools called
platform_choice_tipsSimilar items sold for $220, $245, $210 and $260 — what should I ask?
Tools called
estimate_by_comparablesWhat kinds of secondhand items tend to hold their value?
Tools called
items_holding_valueWhat's a 'comp' in resale pricing?
Tools called
glossaryAbout
Resalevalue is a fully local secondhand/resale value-estimation methodology — not live pricing data or a market lookup. estimate_depreciation combines a category's illustrative age-based depreciation curve with a condition multiplier to produce a point estimate and a +/-20% range from an original price, age and condition; collectibles/memorabilia is special-cased to say age curves don't apply and rarity/demand dominate instead. category_depreciation_curve shows the illustrative curve (or explains why one category has none). condition_grading returns the right rubric for a category: a general 5-point scale for most goods, a 6-point NWT-based scale for clothing & fashion, and a 6-point mint-based scale for collectibles & memorabilia. price_multiplier_for_condition looks up a single category+condition multiplier. resale_readiness_checklist gives a base checklist plus category-specific extras (e.g. factory-reset guidance for electronics). platform_choice_tips and items_holding_value give general, non-branded guidance. estimate_by_comparables turns 2+ real sale prices you supply into a median/range-based estimate — the one tool that's pure arithmetic on your own numbers, not a curve. glossary defines comps, depreciation, NWT and more. Every estimate is explicitly framed as illustrative methodology, never a live quote or an appraisal.
Sources: General, illustrative depreciation-curve and condition-grading methodology by category, and a comparables calculator run on prices you supply yourself. Not live marketplace pricing data, not a valuation service, and not an appraisal. Zero upstream calls; nothing stored.
Privacy
The publisher, Unify Dynamics LLC, states that tool inputs are processed in memory and not retained.
Data not collectedNo account, no profile, no stored prompts or results.
What it can do
10 tools, grouped by job. Every one is read-only or compute-only.
- Estimate depreciationCombines a category's age-based depreciation curve with a condition multiplier into a point estimate and range for one item's resale value.
- Category depreciation curveA category's general age-based depreciation curve (illustrative % of original value retained at several ages).
- Price multiplier for conditionJust one condition grade's price multiplier and description for a category.
- Estimate by comparablesComputes median, mean and a suggested range from real recent comparable sale prices you supply — usually a better estimate of achievable resale…
- Condition gradingThe condition-grading rubric for a category — a general 5-point scale for most goods, a dedicated NWT-to-poor scale for clothing, and a dedicated…
- Resale readiness checklistCategory-tailored tips to maximize the resale value you can actually achieve before listing an item.
- Platform choice tipsGeneral, non-brand-specific guidance on choosing between a general marketplace, a specialty marketplace, consignment, or a local/in-person sale.
- Items holding valueThe general pattern of which categories tend to hold or gain value over time versus depreciate steeply — educational, not a guarantee for any…
- Categories listEvery resale category Resalevalue covers.
- GlossaryDefinitions of resale terms — depreciation curve, comps, condition grading, patina, consignment, provenance, floor value.
Information
PublisherUnify Dynamics LLC
CategoryEveryday life · Shopping
LanguagesEnglish
Built forGlobal (methodology is general; currency-agnostic)
CompatibilityAny MCP client · any agent · REST
Version0.1.0
MCP endpoint
https://resalevalue.connectorbay.com/mcpREST APIopenapi.json
CountryWorldwide
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Documentation
Back to topWhat Resalevalue is for
"What's this actually worth used?" — a fully local secondhand/resale value-estimation methodology, not a live pricing lookup. It gives you a defensible, category-aware way to reason about depreciation and condition instead of guessing.
What it does
estimate_depreciation combines a category's illustrative age-based depreciation curve with a condition
multiplier to turn an original price, age and condition into a point estimate and a +/-20% range. Collectibles &
memorabilia is special-cased: age curves don't meaningfully apply there, so the tool says so and points to
rarity/demand/authentication instead of a curve. category_depreciation_curve shows the illustrative
percent-of-original curve for a category by age (or explains why one has none). condition_grading returns the
rubric that actually matches how the category is graded in practice: a general 5-point scale (new/like-new/good/
fair/poor) for most goods, a 6-point NWT-anchored scale for clothing & fashion (new-with-tags through heavily
worn), and a 6-point mint-anchored scale for collectibles & memorabilia (mint through poor/damaged).
price_multiplier_for_condition looks up a single category+condition multiplier directly. resale_readiness_
checklist gives a base pre-listing checklist plus category-specific extras — factory-reset and data-wipe steps
for electronics, for example. platform_choice_tips and items_holding_value give general, non-branded
guidance on marketplace tradeoffs and what tends to hold value. estimate_by_comparables is the one purely
arithmetic tool: give it 2 or more real recent sale prices for similar items and it returns the median, range and
a suggested-price band — your numbers, not a curve. categories_list and glossary (comps, depreciation, NWT,
and more) round it out.
What it is not
Not a marketplace price lookup, not a live valuation or appraisal service, and not tied to any specific platform
or brand. Every depreciation curve and condition multiplier is illustrative methodology — a reasonable starting
point for a conversation about value, not a guarantee of what an item will actually sell for. estimate_by_
comparables is only as good as the comparable prices you supply.
Privacy policy
Back to topResale Value — Privacy Policy
Effective 26 September 2026. Unify Dynamics LLC ("we", "us"), Menlo Park, California.
What Resalevalue is. Resalevalue is a connector (an MCP server and REST API) that AI assistants and personal agents call on your behalf for a fully local secondhand/resale value-estimation methodology. You interact with your assistant; the assistant sends us only the arguments needed for that one calculation.
What we receive. The arguments of each tool call — a category, an original price, an age, a condition grade, a list of comparable sale prices, or a glossary term — the technical headers needed to serve the request (an IP address or a client identifier supplied by the assistant, and a Pro API key if you have one), and standard server logs.
Everything is computed locally and nothing is stored. No request is forwarded to any third party, including any marketplace or retailer — there is no upstream call at all — and no item, price, or query is logged in request bodies, recorded, or used to train anything.
What we do not receive or store. We do not receive your conversation with the assistant, your name, or what specific item you're valuing beyond the bare inputs above, and we do not build a profile from your queries: each request is answered independently and nothing carries over between requests. Rate-limit counters (a client identifier and timestamps) are held in memory for at most 24 hours. Hosting-provider access logs, which contain IP addresses and request paths but not request bodies, are retained for up to 30 days for security and abuse prevention.
Sub-processors. None — every calculation runs locally on the server. Hosting: Vercel (United States regions).
Legal bases and your rights. Our processing is necessary to provide the service you request through your assistant. Because we store no personal data beyond short-lived logs, requests to access, correct or delete personal data are usually satisfied automatically; you can still contact agent@connectorbay.com and we will respond within 30 days. We do not sell or share personal information and do not use your data to train models.
Children. Resalevalue is a general-audience service operated by the adult using the assistant.
Changes. We will post changes here with a new effective date.
Terms of service
Back to topResale Value — Terms of Service
Effective 26 September 2026. These terms govern use of the Resalevalue connector ("the Service") operated by Unify Dynamics LLC ("we", "us").
- The Service. Resalevalue returns a fully local secondhand/resale value-estimation methodology — illustrative depreciation curves and condition-grading rubrics by category, a comparables-based price calculator run on prices you supply, general tips, and a glossary. It is accessed through an AI assistant or directly over MCP or HTTP.
- Illustrative methodology, not a valuation or appraisal. Depreciation curves, condition multipliers and
resulting estimates are general, illustrative figures for reasoning about resale value. They are not a live
marketplace price lookup, a professional appraisal, or a guarantee of what any specific item will actually
sell for, which depends on true condition, local demand, timing, and factors this Service cannot see.
estimate_by_comparablesoutput is only as reliable as the comparable prices you provide. - Not tax or financial advice. Any reference to value, depreciation or loss is general orientation, not advice about your specific tax situation.
- Acceptable use. Automated use within the published rate limits is welcome.
- Availability. The Service is provided "as is" without warranty. We may change, limit or discontinue it at any time.
- Data. Our Privacy Policy describes what we process. In short: your inputs are used only to compute one response, and nothing is stored.
- Pro keys. Optional Pro API keys are issued at our discretion, are personal to the holder and may be revoked for abuse.
- Liability. To the fullest extent permitted by law, Unify Dynamics LLC is not liable for any loss arising from a pricing, listing or selling decision made using this Service's output. Our total liability is limited to US $100.
- Governing law. California law; venue in San Mateo County, California.
- Contact. Unify Dynamics LLC · agent@connectorbay.com · https://connectorbay.com/resalevalue
Support
Back to topResale Value support
Email agent@connectorbay.com. We answer within two business days.
- MCP endpoint:
https://resalevalue.connectorbay.com/mcp - REST API:
https://resalevalue.connectorbay.com/openapi.json - Live status: https://resalevalue.connectorbay.com/health
When you report a problem, include the question you asked your agent, roughly when, and which agent you used (for example Claude, ChatGPT or Gemini). Never send us passwords, account numbers or ID numbers. Resale Value never asks for them.