Boone County presents a cash-flow-versus-resilience tension. Measured rent and appreciation signals support screening, but out-migration, covered-job softness, property taxes and inland flooding make the headline yield incomplete. A rental investor should investigate parcel-level taxes, insurance, condition and tenant demand; any case relying on appreciation or a county median deserves caution. Zillow measures county home values; FHFA is a repeat-transaction appreciation index, so their observations are not interchangeable. This is county evidence, not evidence that Boone represents Rockford.
Zillow’s median home value is $290,551, and published median asking rent is $1,804 per month, producing a reported 7.45% gross yield before costs. That is measured market rent, not HUD inference: the two-bedroom FMR is $1,175, a payment standard rather than an asking-rent estimate. Zillow’s annual price change is 6.68%; FHFA’s annual repeat-transaction HPI change is 7.62%. They point in the same direction but use different methods and vintages, so must not be blended. Effective property tax is 2.18%, with median annual tax of $4,735. Gross yield is therefore only a screening measure; insurance, repairs, vacancy, management and financing costs are unpublished.
Realtor.com covers the MLS listing market, not closed sales. Listing prices rose year over year, active supply increased, marketing time lengthened, price reductions were visible, and pending listings exceeded active listings; these describe visible competition, not proven buyer demand. Net migration was -175 households, with average AGI of $67,459 for inbound movers versus $69,975 for outbound movers. Investors made 24 of 585 purchases, a 4.10% share. This does not show heavy investor competition, but rental-demand depth remains unresolved.
Modeled annual building-value loss is 0.12%, not a parcel-specific dollar loss; with inland flood dominant, verify flood-zone status, elevation, drainage, coverage and deductibles. QCEW reports 11,309 annual average covered jobs in the county, down 1.88%, while average weekly wage growth was 3.28%. It is workplace covered employment, not resident employment, unemployment or a metro series; Trade, transportation, and utilities is the largest disclosed private supersector, not the whole economy. Unpublished property expenses, insurance, vacancy, lease terms, closed-sale comps, financing and resident labor measures prevent net-yield, debt-service and durable-demand underwriting. Obtain those before relying on the gross screen.