Our editorial standards
1. Source hierarchy
Every accuracy claim, dollar range, regulatory rule, or methodology detail in a Twellie guide is sourced from one of three tiers, in this order:
- Tier 1 — Primary regulatory and standards sources. USPAP (Uniform Standards of Professional Appraisal Practice), the FFIEC AVM Guidance (2010), the OCC Comptroller's Handbook, the Fannie Mae and Freddie Mac Selling Guides, the CFPB Loan Estimate and Closing Disclosure rules, RESPA, the FHFA House Price Index methodology, the NAR settlement (March 2024) consent decree, HUD/FHA program docs.
- Tier 2 — Vendor-published methodology disclosures. Zillow Research blog accuracy disclosures, Redfin Data Center, the AppraisalBuzz reports, Quantarium and HouseCanary published methodology papers, CoreLogic AVM benchmarking, Black Knight's transaction databases.
- Tier 3 — Reputable secondary reporting. Inman, HousingWire, RisMedia, NerdWallet, Bankrate, Rocket Mortgage research — used only as supporting context, never as the sole source for a numerical claim.
We do not cite social-media threads, anonymous forum posts, or unverified vendor PR claims. If a number doesn't come from a Tier 1 or Tier 2 source, we either find one or we leave the number out.
2. Drafting against a structured outline
Every guide is drafted against a fixed brief that specifies the primary keyword, the secondary keywords, the target word count (2,500–3,000 for pillar guides; 600–900 for glossary entries), the required schema (Article + BreadcrumbList + FAQPage), and the AEO-compliance requirements (first-200-words extractive answer, 5 FAQs that mirror real natural-language queries, 4–8 in-prose internal links, 1+ comparison table). The brief exists so different writers produce consistently structured content; the brief does not specify the conclusion.
3. Fact-checking against primary sources
Before publication, every numerical claim, regulatory citation, and accuracy benchmark in the draft is verified against the cited primary source. Claims that don't survive verification get cut. Claims that get partially-verified get re-worded to match what the source actually says. The most common cut: vendor-published accuracy claims that don't disclose the benchmark set or the active-vs-off-market split.
4. Peer review by transactional experience
No guide is published without sign-off from at least one team member who has either (a) personally completed a US home transaction in the last 36 months, (b) holds an active real-estate license or has held one in the last 60 months, or (c) has worked as an appraiser, mortgage underwriter, or transaction-coordination professional. Reviewer name and role appear in the byline.
5. Freshness review every 90 days
Every guide is reviewed every 90 days for stale data — accuracy benchmarks, average closing-cost percentages, regulatory status (e.g., post-NAR-settlement specifics), and dollar ranges that drift with the rate environment. The reviewed date is updated at the top of every guide, and an updated dateModified ISO timestamp is emitted in the Article JSON-LD on every render so AI engines see the freshness.
Disclosure: how we make money, and what we don't sell
Twellie sells one product: a $50 per-property AI report. We also sell an Enterprise tier ($199/month) for high-volume users (real estate investors, relocation services, internal corporate use). That's the entire revenue stream.
We do not:
- Sell user data to mortgage brokers, lenders, agents, insurance providers, or any third party.
- Earn referral commission on agent introductions, lender introductions, inspector introductions, title-company introductions, or any service-provider introductions.
- Run affiliate links in our content. When we cite a tool (Zillow, Redfin, HouseCanary, Quantarium, Opendoor, etc.), we earn nothing if you click through.
- Trade or hold positions in any specific property. Twellie has zero financial interest in whether any given home transaction closes.
The full data and privacy disclosure is at our privacy policy; the full terms are at our terms of service.
Corrections policy
If you find a factual error in any guide — a wrong number, an out-of-date regulation, a misattribution to a primary source — email editorial@twellie.com. Verified corrections are made within 5 business days. The corrected guide displays a "Last reviewed" timestamp and, when the correction is material, an explicit Corrected: [date] — [what changed] footnote in the body of the guide.
AI-assisted writing disclosure
Some guides on this site are drafted with AI assistance — typically a structured-outline pass, a first-draft generation against the brief, and an editor review. Every AI-assisted draft is then fact-checked against primary sources by a human editor and peer-reviewed by a team member with transactional experience. We do not publish AI-generated text that has not been human-reviewed for factual accuracy. The standards above (source hierarchy, fact-checking, peer review) apply identically to AI-assisted drafts and to human-written drafts.
What we get wrong (and what we'll do about it)
We are a 2026 product publishing in a fast-moving regulatory and market environment. The following are honest known limitations of our content as of :
- Post-NAR-settlement market data is still sparse. The settlement only became operational on August 17, 2024, so commission-norm data, buyer-paid-fee distributions, and the impact on closing costs are based on early reporting (Inman, HousingWire, NAR member surveys) and may revise as more transactions close.
- State-specific content covers 5 of 50 states. California, Texas, Florida, New York, and Illinois are live; the remaining 45 states are on the Q3 2026 roadmap. State-specific quirks (transfer tax, attorney-required closing, recordation fee, homestead exemptions) should be cross-checked against the state real-estate commission's current bulletins until then.
- Rural and atypical-property accuracy is meaningfully worse than urban tract-suburban accuracy. AVMs depend on comparable-sales density. We disclose this in every guide that touches accuracy; if you're buying a 40-acre farm, the AVM number is a starting point, not a verdict.
Contact for editorial questions
Email editorial@twellie.com for: factual corrections, source-attribution corrections, requests for additional disclosure, fair-use citation requests, and pitches for guest-author guides (we accept ~2 per quarter from licensed appraisers, real-estate attorneys, and mortgage underwriters).