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Check your car deal before you sign
Win with AI — let us audit your deal and negotiate for you.
Powered by our deterministic 50-state statutory & math engine (Rule v2026.10 — never hallucinated AI numbers) plus ready-to-send buyer counter-offer templates you copy and send yourself.
Upload a photo of a dealer worksheet, buyer’s order or lease sheet. We read every line, check the math and your state’s rules, and show what looks off. We never contact the dealer. Educational only, not financial or legal advice. Verify all figures with your lender and dealer.
🔗 Paste the Link to the Car You Want to Buy (We Auto-Fill Everything for You)
Don’t want to type? Paste the dealer’s vehicle webpage link (or AutoTrader / Cars.com / CarGurus link) below. We automatically pull the Year, Make, Model, Trim, VIN, Mileage, Advertised Internet Price, Dealership Name & ZIP, Google Reviews, Free Carfax Link, and all Listing Photos:
Action A: Take a Photo or Upload Dealer Sheet (or Carfax PDF)
Snap a photo or upload a PDF of your dealer quote, worksheet, buyer’s order, lease sheet, or Carfax report — or tap a sample quote below to see it work in 1 tap.
Lay the sheet flat, fill the frame, and avoid glare.
We never sell your name, phone, or email to dealerships. Deterministic math + state statutes only—never hallucinated AI numbers.
Your file is encrypted and deleted after 30 days, or now with one tap. We read it with our own software; no person reads it.
Action C: No Quote Yet? Get 3 Dealer Quotes via Text/Email (Free OTD Request Generator)
Don’t walk into a showroom without a written Out-the-Door (OTD) breakdown first. Enter the car you want below and copy a ready-to-send email or text message to request an itemized OTD worksheet from 3 nearby internet sales desks:
3-Step Deal Desk Workflow: Step 1: Send the message above to 3 dealers to get itemized written OTD quotes. Step 2: Upload or type their reply into Action A or B above to flag hidden add-ons, doc-fee overages, and tax/APR padding. Step 3: Send the pre-filled counter-offer text or compare all 3 quotes side-by-side.
3. Your Deal Audit & Negotiation Vault
What surprised you most? (optional)
Quick question: what stopped you from running a full check today?
How VaultRubric Deal Desk Compares to Human Brokers, Chatbots & Lead-Gen Sites
Most car-buying sites either sell your phone number to dealerships as a sales lead or charge $500–$1,000+ with a multi-day wait. Here is how VaultRubric compares:
| Feature / Protection | VaultRubric Deal Desk ($39 Audit Kit / $129 Full Negotiation) | Human Deal Concierges (e.g. Delivrd $1,000 flat fee) | Chatbot Subscriptions (e.g. CarEdge $49/mo–$999) | Lead-Gen Marketplaces (e.g. TrueCar / Edmunds) |
|---|---|---|---|---|
| One-Time Price (No Recurring Subscription) | $39 Full Audit Kit / $129 Done-For-You Full Negotiation (One-Time, No Passes) | $1,000 flat fee | $49/mo recurring subscription to $999+ | Free to buyer (funded by dealer lead/ad fees) |
| Turnaround Speed | Instant (60 seconds on screen, 24/7) | 7–15 business day wait queue | Self-serve chat / multi-step modules | Instant dealer lead routing (expect phone/text calls) |
| Used Cars, Leases, Commercial Trucks & Ag Equipment | Yes — Used Cars, New Cars, Leases, Class 3–8 Trucks & Ag Equipment | Often paused on used cars; new-car focus | Passenger cars only (no IRC § 4051 FET or Ag equipment) | New & used passenger listings only |
| 50-State Statutory Tax, Trade-In Credit & Doc-Fee Cap Math | Deterministic 50-state + DC rule engine (Rule v2026.10) | Manual human broker estimate | LLM chatbot (can hallucinate state tax/cap rules) | Does not audit dealer F&I worksheets |
| Lead-Sale Privacy | 100% Buyer-Paid — never sells your name, phone, or email to dealers | Contacts dealers on your behalf | Account signup required | Sells buyer contact info to participating dealers |
What the checker looks for
- Market adjustment or a price over the sticker. A dealer markup, not a government or lender charge.
- Doc fee over your state’s limit. 17 states limit it; we use our doc fee by state table.
- Add-ons you didn’t choose. VIN etching, nitrogen, paint and fabric protection, GAP, service contracts and similar products are optional.
- Tax that doesn’t match the state rule. Loans use our car sales tax rules (trade-in credit, rebates, Tennessee single-article tax); leases use the 50-state lease calculator.
- APR or money factor markup. Compared with your own bank or credit union offer, or the lender’s buy rate if the sheet shows it.
- A payment, amount financed or due-at-signing that’s higher than the sheet’s own lines add up to (payment packing).
- Rebate short of what you were promised, a lowball trade-in, and negative equity rolled into the deal.
How the dollars are figured
- Loan payment = amount financed × r ÷ (1 − (1 + r)−months), r = APR ÷ 12, rounded to the cent.
- Amount financed = price + market adjustment + doc fee + add-ons + tax + title fees − cash down − rebates − (trade allowance − payoff).
- Lease payment = (adjusted cap cost − residual) ÷ months + (adjusted cap cost + residual) × money factor, plus your state’s lease tax (or the lease tax rate on your sheet, if you type it).
- Cash purchase: out-the-door price = price + market adjustment + doc fee + add-ons + tax + title fees − rebates. No term or APR needed. Example only, your deal will differ: 41,250 + 899 doc + 2,490 add-ons = 44,639; at an assumed 8.25% tax that’s 3,682.72, plus 325 title = 48,646.72.
- Overcharge = what the dealer’s deal costs you in all (cash down plus every payment) minus the same deal with each flagged problem fixed. Negative equity stays in both: it’s real debt, not a dealer charge.
Sources & as-of dates
- State vehicle sales tax, trade-in credit and rebate rules: VaultRubric car sales tax by state (state revenue departments; checked Oct. 2026).
- Lease tax by state: VaultRubric lease calculator (state revenue departments; checked Oct. 20, 2026).
- Doc fee limits: VaultRubric doc fee by state (checked Oct. 18, 2026).
- Average rate: Federal Reserve G.19, 60-month new car loan rate at commercial banks (FRED RIFLPBCIANM60NM), August 2026 (FRED).
- Add-ons are optional: CFPB; dealer rate markup: CFPB auto loan key terms.
FAQ
Does VaultRubric send anything to the dealer?
No. You get an educational summary of the sheet. We never contact a dealer or lender.
What happens to the photo of my sheet?
It's encrypted with a key only our app holds and deleted after 30 days, or right away when you tap Delete my uploaded sheet now. Our own software reads it; no person does, and it isn't sent to an AI service.
What's free and what's paid?
The quick scan is free: the top 3 issues, without dollar amounts. The full check is $39 one-time for the Full Audit Kit (multi-dealer 2-5 scenario comparison & winner pick + full line-by-line audit + 8-point listing photo checklist + copy-paste reply kit) or $129 one-time for Full Negotiation (Hire Us to Negotiate For You — everything in the $39 Full Audit Kit plus done-for-you written multi-dealer negotiation) (never auto-renews): every flag with dollars, the estimated overcharge, a target based on the lines above (educational estimate) and a line-by-line summary. Yearly VaultRubric Pro ($59 a year) includes unlimited full checks once your first payment goes through (none during the free trial). Monthly Pro ($7 a month) includes 1 full check each billing month once your first payment goes through (none during the free trial), and an unused check doesn't carry over.
Is this financial or legal advice?
No. Educational only, not financial or legal advice. Verify all figures with your lender and dealer. It covers the math and the state rules we can source; your signed contract and your state's law decide.
Educational only, not financial or legal advice. Verify all figures with your lender and dealer.