Per-ZIP figures are estimated from real ZIP-code geography (proximity to major metros, coastlines, mountain ranges, known fault zones, and interpolated annual sunshine hours from ~55 reference cities) layered on state-level baselines - illustrative, not authoritative. Median household income is estimated from real IRS tax-return data per ZIP code (2022); median home value is from the Census Bureau's American Community Survey (owner-occupied homes, capped at $2,000,001 by the Census itself, so very expensive ZIPs are understated). "Comfortable income" is an illustrative $100k/year national rule-of-thumb for a family of 4, adjusted for local cost of living, and "Affordability" is median income as a % of that. "Housing affordability" is a separate measure: median income as a % of the median home value in that ZIP. "Housing budget" filters ZIPs by home value against the US national median ($370,000). "Detached single-family home" checks that budget against a higher, single-family-specific price estimate instead of the blended median - ACS's median blends every housing type (including condos), so it understates what a detached house actually costs in condo-heavy ZIPs; the estimate scales up based on each ZIP's real share of housing units that are detached (Census ACS table B25024). "Fit" reflects job-market strength for working, retiree-friendliness for retired, and a blend of both for semi-retired.