Every guide on The Dwelling Index follows a structured research process. This page explains how we gather information, verify claims, and maintain accuracy across our content.
We prioritize sources in the following order:
Verified
The claim has been confirmed against at least one primary source and cross-checked against a second independent source. The source is cited.
Estimated
The figure is derived from available data but involves calculation, interpolation, or judgment. The basis and methodology are explained.
Last updated
The date when material changes were made to the page — new data, revised figures, or added sections.
Last verified
The date when the editorial team most recently reviewed the page against current sources and confirmed it remained accurate, without necessarily making changes.
Primary Sources
Process
We read primary legislation and municipal code — not summaries of summaries. When a state passes new ADU legislation, we review the enrolled bill text, cross-reference it with the existing code it amends, and verify effective dates before publishing. We do not rely on press releases or news articles as primary sources for legal claims.
Primary Sources
Process
Cost figures are verified against at least two independent data points before publication. When we publish a range, we specify the market, timeframe, ADU type, and what is included or excluded. We distinguish between 'base price' (what a company advertises) and 'all-in installed cost' (what the homeowner actually pays). We never present a single cost figure without context.
Primary Sources
Process
We evaluate prefab ADU companies based on pricing transparency, published track record, service area, build type, and verifiable customer outcomes. Companies are ranked on editorial criteria — not on whether they have an affiliate relationship with us. We re-verify company data (pricing, service areas, availability) before each major update.
Primary Sources
Process
Financing guidance is grounded in the actual agency guidelines that govern lending decisions — not lender marketing materials. When we explain a financing path, we cite the specific guideline section. We clearly distinguish between what the guidelines allow and what individual lenders may require (lender overlays). We never present a financing option as universally available without noting eligibility conditions.
Every published guide is reviewed on a regular cadence. Content in fast-changing areas — state legislation, company pricing, and financing program availability — is reviewed more frequently.
When a significant change occurs — new state legislation, a company price change, or an agency guideline update — we prioritize updating affected guides promptly and note material updates at the top of the article.
The "last verified" date displayed on each guide reflects the most recent date the editorial team confirmed the content against current sources.