Private seller vs. dealer: the true cost comparison

The short version

Buying from a private seller usually means a lower price and no dealer fees. In some states, like Arizona, there is also no sales tax. In exchange, you take on more of the risk and paperwork. There's no dealer to handle the title, usually no warranty, and you have to arrange your own loan.

The price gap alone doesn't tell you which deal is cheaper. Compare the out-the-door cost of each: price, tax, government fees and dealer fees. Then add what the private sale costs you in other ways: an inspection, a possibly higher loan rate, and losing the dealer's trade-in tax credit.

Houston: same tax, fewer fees

Texas charges a 6.25% motor vehicle sales tax whether you buy from a dealer or a private seller. In Harris County, the title fee is $33, plus $2.50 to transfer a current registration. Suppose the same car is listed for $20,000 at a dealer and $18,500 by its owner. Dealer prices include reconditioning, overhead and profit, so private asking prices are often lower, but not always.

Dealer: $20,000 + $1,250 tax + $35.50 title and registration + a $225 doc fee = $21,510.50 out the door. With $3,000 down, that's $382.54 a month. Open the dealer example.

Private seller: $18,500 + $1,156.25 tax + $35.50 = $19,691.75. With $3,000 down, that's $344.96 a month. Open the private-seller example.

The private deal costs $1,818.75 less up front and about $2,255 less over the loan. The $225 doc fee is the amount Texas regulators presume is reasonable for a financed sale. Check your quote for the actual number.

The Texas catch: tax on the car's value, not just your price

On a private sale, Texas taxes the greater of what you paid or 80% of the car's standard presumptive value (SPV), a value the state sets from used-car sales data. Paying $12,000 for a car with an $18,000 SPV means tax on $14,400: $900, not $750. A low price on the bill of sale doesn't lower the tax.

If the car really is worth less, for example because of damage or high miles, Texas accepts a certified appraisal (Comptroller form 14-128) filed with your title application. You have 30 calendar days from the purchase to title the car and pay the tax at the county tax office, using Form 130-U.

Phoenix: no sales tax on a private sale

Arizona's sales tax, called the transaction privilege tax, is a tax on businesses. The Arizona Department of Revenue says a "casual activity or sale" isn't taxable, so buying a car from a private owner carries no sales tax. Dealer sales are taxed: in Phoenix, 5.6% state, 0.7% Maricopa County and 2.8% city tax on the first $14,338 of a single item, with the city rate dropping to 2.0% above that.

Take the same car at $18,000 from a dealer or $16,500 from its owner. Arizona's vehicle license tax and registration fees apply either way, so they're left out of both totals.

Dealer: $18,000 + about $1,609 tax + a $499 doc fee (an example; use the fee on your quote) = about $20,108. With $3,000 down, that's $353.55 a month. Open the dealer example.

Private seller: $16,500, no tax and no doc fee. With $3,000 down, that's $278.99 a month. Open the private-seller example.

That's about $3,608 less up front and about $4,473 less over the loan. If the City of Phoenix later bills you vehicle use tax on a private purchase, its guidance lists a private-party purchase as a reason the bill may be in error. You have 45 days to dispute it.

What the dealer gives you for the extra money

A trade-in tax credit. In Texas and Arizona, trading your car in to the dealer means you pay tax only on the price minus the trade. In Houston, an $8,000 trade-in saves $500 in tax. With a private purchase you sell your old car yourself, and there's no credit. See how the trade-in credit works by state.

Disclosures and sometimes a warranty. Dealers must post the FTC's Buyers Guide on used cars, which says whether the car comes with a warranty or is sold "as is." The FTC notes that private sellers generally don't have to use it, and a private sale "probably will be on an 'as is' basis."

Paperwork and financing in one place. The dealer handles the title transfer and can arrange a loan on the spot. That's convenient, but the rate can be marked up. See how dealers hide the real numbers.

Financing a private-party purchase

Many banks and credit unions make private-party auto loans, but not all of them do, and some charge more than for a dealer purchase. Get pre-approved before you start looking, so you know your rate and how the lender pays the seller.

In the Houston example, a rate one point higher (9.81%) adds about $8 a month. The private deal is still about $1,767 cheaper over the loan. See how APR changes your payment.

Title and lien risks, and how to avoid them

The seller still owes money on the car. If there's a loan, the lender has a lien and may hold the title. Pay the lender directly, ideally at the seller's bank, and don't hand over the full price until you have a lien release or a clear title.

The person selling isn't the owner. Make sure the name on the title matches the seller's photo ID, and the VIN on the title matches the car, both on the dashboard and on the driver's door jamb.

A branded title or hidden history. Check the VIN through an approved NMVTIS provider for salvage, flood or rebuilt brands before you pay. Our salvage vs. rebuilt title guide explains what each brand means.

No inspection. Pay for an independent pre-purchase inspection. It's cheap next to a surprise repair, and a seller who won't allow one is telling you something.

A quick way to decide

Put both deals in the car payment calculator: price, tax, fees, and the loan rate you'd actually get for each. Then subtract the inspection cost and, if you'd be trading in, the trade-in tax credit you'd give up. If the private deal still comes out well ahead and the title checks out, it's usually the better buy. If the gap is small, the dealer's paperwork, disclosures and possible warranty may be worth the difference. Our out-the-door price guide shows how to read a dealer quote line by line.

Sources

Texas Comptroller, Motor Vehicle Sales and Use Tax. Harris County Tax Office, Buying a Used Motor Vehicle. Texas Office of Consumer Credit Commissioner, documentary fee rule, 7 TAC § 84.205 (2024). Arizona Department of Revenue, Conducting Taxable Retail Activity. City of Phoenix, Combined Tax Rate Chart (January 2026) and Vehicle Use Tax. Federal Trade Commission, Buying a Used Car. U.S. Department of Justice, National Motor Vehicle Title Information System. Experian, average used-car loan rates by credit score (Q2 2026). Checked October 2026. Prices are examples, payments were calculated with LotGauge's calculator, and none of this is tax or legal advice.