Methodology
Methodology & data sources
Our estimates are only as good as our data. Here's exactly where it comes from, how we verify it, and how we flag what we haven't.
Anyone can run a depreciation formula. The harder, more valuable part is the state-specific legal facts — the vehicle sales-tax rate, the annual registration fee schedule, whether the state levies a personal property tax on vehicles, and inspection requirements. Those come from statutes and official agency schedules, not guesses, so we treat them with care and show our work.
Where each figure comes from
- Vehicle sales-tax rates: each state's Department of Revenue or taxation authority and the underlying statute.
- Annual registration fees: each state's DMV or Department of Motor Vehicles published fee schedule.
- Vehicle personal property tax: state revenue department rules governing which counties or municipalities levy the tax and the applicable rate method.
- Vehicle inspection requirements: each state's DMV or equivalent safety and emissions authority.
- Title fees: state DMV published schedule.
- Depreciation curves, insurance, maintenance, fuel: standard industry-published averages from sources like Consumer Reports, AAA, and J.D. Power — clearly presented as estimates, not facts specific to any vehicle.
The data gate: verified vs. estimated
Every state record carries a verified flag and the date we last checked it against the official source. This drives a hard rule built into the build itself:
- Source-verified records show a badge with the citation, the official source link, and the date we confirmed it. These pages are indexable.
- Estimated records show an amber "not yet source-verified" badge. Those pages are noindexed and excluded from our sitemap — so an unconfirmed figure can never rank in search as authoritative.
As of June 2026, 0 states are source-verified and 51 are still estimates being verified on a rolling basis.
How often we review
States adjust DMV fees and tax rates, usually around their legislative cycles. We re-review the dataset at least annually and monitor known changes in between. Even so, fees can change between our review date and when you're reading this — which is why every page says to confirm the current amount with your state DMV or a licensed professional before purchase.
What we don't do
We don't rely on Wikipedia, unsourced blogs, or AI-generated numbers for any verified figure. We don't scrape or copy competitor data. And we don't claim expertise we don't have — CarOutlay publishes estimates and general information, not financial or legal advice for your specific situation.
Partner relationships
When we link to a partner (for example, to compare insurance quotes or refinance rates), it's a clearly-labeled outbound link to the partner's own site, and we may earn a flat referral fee if you use it. A partner relationship never changes a data figure, a ranking, or what we estimate. See how we make money for the full disclosure.