Trust · How We Know
Every number on this site can show its work
CandidCost turns public data into tools. That only means something if you can check it. Here is the evidence standard we hold ourselves to — the same one a journalist or examiner could audit.
The source hierarchy
We rank every input by how authoritative it is. Published figures draw from the highest tier available, and the tier travels with the number wherever it appears.
HMDA, FRED, Census ACS, CFPB regulations, county records
Official industry statistics with published definitions
Named surveys that publish their methodology
Reputable press — only to establish that an event happened
What backs each figure
A named source
Publisher, dataset, and vintage — with a link to the public record. No anonymous "studies show."
A versioned methodology
Every calculation carries a version tag (e.g. true-cost-v2). Change the math, and the version changes with it.
A ledger receipt
Data ingests and methodology changes are recorded as append-only events, each with a content hash you can reference.
The ledger
Behind the site is an append-only log. When we ingest a dataset or ship a methodology change, we write an event with a hash. Nothing is edited in place — corrections are new entries, so the history stays intact.
Each tool shows an "as of" date and flags data that has passed its freshness window.
- Oct 5, 2026
NAIC homeowners insurance premiums
e548…d19a · 51 rows
- Oct 5, 2026
Source & methodology registry snapshot
d3b9…6537 · 12 rows
- Oct 4, 2026
Ledger chain-head anchored
11c4…d387 · 17 rows
- Oct 4, 2026
HMDA loan aggregations
2d9f…782a · 51 rows
- Oct 4, 2026
Source & methodology registry snapshot
cecb…f959 · 12 rows
- Oct 4, 2026
HMDA LAR fee & rate percentiles
287c…9895 · 200 rows
- Oct 4, 2026
Source & methodology registry snapshot
4a2b…be42 · 12 rows
- Oct 3, 2026
Census effective property-tax rates
bb89…44b4 · 3,135 rows
Verify it yourself
What the ledger proves — and what it does not
- It proves that the data and methodology history published here has not been edited, reordered, or backdated after the fact: every receipt commits to its predecessor, and the chain head is witnessed outside our control.
- It does not prove that a source was right, that an estimate matches your situation, or anything about you — no consumer input ever touches the ledger, hashed or otherwise.
Run the independent verifier
The verifier shares no code with the ledger writer — it re-implements the hashing from the published spec and audits every receipt:
git clone https://github.com/RCOLKITT/candidcost
npx tsx scripts/verify-ledger.tsLatest external anchor: 0e0a18de03cf… covering 17 datasets, Oct 4, 2026 · OpenTimestamps proof recorded · status: partial
Data freshness
Traceable is not enough — data has to be current. Every dataset is held to a 90-day policy. Once a figure passes it, it is queued for re-verification and flagged wherever it appears.
HMDA LAR fee & rate percentiles
90b4…bbee · 1,020 rows · last verified Jul 4, 2026
HMDA loan aggregations
919d…c5eb · 204 rows · last verified Jul 4, 2026
Census effective property-tax rates
9a76…858f · 102 rows · last verified Jul 5, 2026
Census effective property-tax rates
b9e5…64be · 3,133 rows · last verified Jul 6, 2026
Down payment assistance directory
bdd7…0d6a · 90 rows · last verified Sep 6, 2026
fema:flood_claims:2026
686f…8f9b · 255 rows · last verified Oct 2, 2026
Fee & Rate Index edition published
56e6…7e83 · 212 rows · last verified Oct 1, 2026
FRED mortgage rate series
1e38…c828 · 1,976 rows · last verified Oct 1, 2026
FRED mortgage rate series
d0b8…4457 · 1,976 rows · last verified Oct 1, 2026
report:fees-and-rates
9fec…b548 · 204 rows · last verified Oct 1, 2026
Census effective property-tax rates
d0b6…d12c · 204 rows · last verified Oct 3, 2026
Census effective property-tax rates
bb89…44b4 · 12,540 rows · last verified Oct 3, 2026
HMDA LAR fee & rate percentiles
287c…9895 · 1,820 rows · last verified Oct 4, 2026
HMDA loan aggregations
2d9f…782a · 255 rows · last verified Oct 4, 2026
Ledger chain-head anchored
11c4…d387 · 283 rows · last verified Oct 4, 2026
Source & methodology registry snapshot
d3b9…6537 · 716 rows · last verified Oct 5, 2026
NAIC homeowners insurance premiums
e548…d19a · 357 rows · last verified Oct 5, 2026
What we are — and what we refuse to be
We explain. We do not advise.
We show the math and the sources. We never tell you what to do, which loan to pick, or what you can afford. Those are your decisions.
No leads. No lender payments.
We are not a lender or broker. We do not sell your information, collect referral fees, or accept payment from lenders to rank or recommend them.
Primary sources
The public datasets and rules behind the tools.
Home Mortgage Disclosure Act (HMDA) Loan/Application Records
Consumer Financial Protection Bureau · public-domain
National Flood Insurance Program — redacted claims (FimaNfipClaims)
Federal Emergency Management Agency (OpenFEMA) · public-domain
15-Year Fixed Rate Mortgage Average in the United States (MORTGAGE15US)
Federal Reserve Bank of St. Louis (FRED) · public-domain
30-Year Fixed Rate Mortgage Average in the United States (MORTGAGE30US)
Federal Reserve Bank of St. Louis (FRED) · public-domain
Dwelling Fire, Homeowners Owner-Occupied Insurance Report — average HO-3 premium by state (2022 data year)
National Association of Insurance Commissioners (NAIC) · restricted
American Community Survey 5-Year Estimates (B25103 real estate taxes, B25077 home value)
U.S. Census Bureau · public-domain
HUD Local Homebuying & Down Payment Assistance Programs
U.S. Department of Housing & Urban Development · public-domain
CandidCost internal derivations (methodology registry, anchors, index editions; key predates the CandidCost rename)
CandidCost · public