{"schema_version":"1","report_id":"r_229-n-whispering-hills-dr-naperville-il-60540","address":{"input":null,"resolved":"229 N Whispering Hills, Naperville, IL 60540","county":"DuPage","state":"IL","pin":"07-14-106-037","lat":41.777747,"lng":-88.178054},"valuation":{"range":{"low":664981.9212188778,"high":774996.2537895193},"range_basis":{"method":null,"half_width_pct":7.6,"target_coverage_pct":55,"sample_size":6621,"calibration_segment":"collar_listed/low"},"uncalibrated_range":{"low":677339.16,"high":754233.92},"midpoint":719989.0875041985,"anchor":{"price":650000.0,"source":"listing","reliability":"high","promoted_from":null,"promoted_from_price":null},"cross_checks":[{"name":"regression","estimate":766000.65,"peers":9,"weight":null}],"steps":[{"name":"nearby_sales","estimate":null,"weight":null,"midpoint_after":715787.0},{"name":"range_calibration","estimate":null,"weight":null,"midpoint_after":719989.0}],"negotiating_position":{"label":"Below Range","suggested_offer_low":650000.0,"suggested_offer_high":650000.0,"basis":"Ask sits at roughly the -14th percentile of the comp-supported range (-15.1% vs. the regression-estimated point value, -9.2% vs. the middle of the range) — below the bottom of the range in a market that favors the seller — high-confidence analysis."},"size_note":null},"condition":{"tier":"A","confidence":"high","source":"listing","basis":["list_to_avm_ratio","ppsf_ratio","prior_sale_time_adjusted","prior_sale_vs_comp_mid"],"rationale":"Estimated from asking $/sqft is 78% of the comp median; list price is 83% of the AVM; last sold $434,000 (2007), ~$763,999 time-adjusted — at/above the comp midpoint, inconsistent with dated/original condition; reads as dated/original. Inferred from market/observational proxies, not an inspection.","flip":null},"confidence":{"label":"Medium","why":[],"would_tighten":[{"text":"Confirming finished basement square footage would narrow the total-finished-sqft-based range.","field":"condition.finished_basement_sqft"}]},"comps":[],"excluded_comps":null,"search":{"radius_mi":null,"widened":null,"window_months":null,"filters":null,"pool_size":28,"returned":28,"kept":null,"excluded":null,"candidates":null,"comps_withheld":null},"tax":{"pin":"07-14-106-037","assessed_value":null,"assessment_year":2025,"exemptions":["general"],"composite_rate":0.061261,"rate_year":null,"rate_adjustment_pct":null,"effective_rate_on_mv":0.0204,"current_annual":10571.88,"projected_scenarios":[{"label":"At ask","price_point":650000.0,"projected_annual":13260.0,"projected_monthly":1105.0},{"label":"Ask -5%","price_point":617500.0,"projected_annual":12597.0,"projected_monthly":1049.75},{"label":"Ask -10%","price_point":585000.0,"projected_annual":11934.0,"projected_monthly":994.5},{"label":"Ask -10% + appeal (-10% AV)","price_point":526500.0,"projected_annual":10740.6,"projected_monthly":895.05}],"projected_increase_pct":25.4,"notes":["The 2025 bill carries only the general homestead exemption ($8,000 off the assessed value, about $466 a year at the 2025 rate), which a buyer who lives in the home can claim too, so none of the current owner's relief is lost on a sale."],"sources":["dupage_gis"]},"listing":{"status":"active","list_price":650000.0,"list_date":"2026-11-04","first_list_date":null,"days_on_market":9,"cumulative_dom":null,"current_period_dom":null,"listing_periods":null,"price_history":[],"source":"feed"},"history":{"sales":[{"date":"2007-09-25","price":434000.0,"arms_length":null,"source":null}]},"market":{"signal":"median price down -4.4% over the window; DOM rising (29→32d, market cooling); ~1.8mo supply (tight)","median_dom":32,"months_supply":1.8,"price_trend_pct":-4.4,"hpi_index_name":"FHFA All-Transactions","hpi_region":"Chicago metro division","hpi_yoy_pct":0.062,"rent_estimate":3783.75,"rent_low":3337.83,"rent_high":4256.69,"rent_confidence":"medium","gross_yield_pct":6.99},"risks":{"flood":{"zone":"X","sfha":false,"known":true},"radon_zone":2,"hazard_ratings":null,"schools":{"district":"Naperville Community Unit District 203","scope":"district","summary":"ELA growth: Near State Average · Math growth: Near State Average","outcomes":null}},"inputs_used":[],"provenance":{"valuation.anchor.price":{"value":650000.0,"source":"listing","tier":1,"as_of":null},"listing.list_price":{"value":650000.0,"source":null,"tier":null,"as_of":null},"tax.composite_rate":{"value":0.061261,"source":null,"tier":null,"as_of":null},"condition.tier":{"value":"A","source":null,"tier":null,"as_of":null},"property.sqft":{"value":2428,"source":null,"tier":null,"as_of":null},"property.beds":{"value":4,"source":null,"tier":null,"as_of":null},"property.baths":{"value":2.5,"source":null,"tier":null,"as_of":null},"property.year_built":{"value":1978,"source":null,"tier":null,"as_of":null},"history.last_sale.price":{"value":434000.0,"source":null,"tier":null,"as_of":null}},"gaps":["Only 0 vacant-land comp(s) found nearby — too thin to compute a land-value estimate for this property."],"attributions":["This product uses the FRED® API but is not endorsed or certified by the Federal Reserve Bank of St. Louis.","County-level housing-market trend data: Realtor.com, retrieved from FRED, Federal Reserve Bank of St. Louis; fred.stlouisfed.org.","Nearby-places data: Overture Maps Foundation Places (overturemaps.org), published under the CDLA Permissive 2.0, Apache 2.0 and CC0 1.0 licenses depending on the contributing source, including Foursquare Open Source Places (Apache 2.0). The data is a snapshot and may omit or still list a business.","Natural-hazard ratings: FEMA National Risk Index (nri.fema.gov), census tract data, December 2025 release (version 1.20). This product uses FEMA data but is neither endorsed nor certified by FEMA.","Storm history: NOAA National Centers for Environmental Information, Storm Events Database.","Contains information licensed under the Open Geo-Spatial Data License – DuPage County.","This product uses the HUD User Data API but is not endorsed or certified by HUD User.","This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.","Reports are provided solely for general business information purposes. No advisory, fiduciary or other relationship is created by any acceptance or use of Reports. The inclusion of Reports with any other materials does not constitute an endorsement by RentCast of any third party or any third-party's products or services. The projected valuation, financial and investment return information, conclusions and other information contained in Reports are based upon tested methodologies for accuracy. However, such information and conclusions are not definitive forecasts, appraisals or opinions of valuations. All such information and conclusions are stated in terms of probability of likelihood based on market factors and information submitted to RentCast, and such information and conclusions are not guaranteed by RentCast and should not be construed as a certified appraisal or valuation, or investment advice. RentCast uses or has used public and/or confidential data and assumptions provided to RentCast by third parties, and RentCast has not independently verified the data and assumptions used in these analyses or data sets. Attributes for properties may be inaccurate because county assessor and property data records do not always include recent additions and/or modifications to property structures. Changes in the underlying data or operating assumptions, or any loss of access to any one or more sources will clearly impact the analyses, information and conclusions set forth in Reports."],"disclaimer":"*AI-generated property analysis using public records and aggregated market data. Estimates are probabilistic — data has gaps, markets move, and nothing replaces eyes on the property. This report is built to inform your own judgment, not replace it. The decision, the due diligence, and the risk are yours. Caveat emptor.*\n\n*Mortgage benchmark rate data (30-year fixed, 10-year U.S. Treasury), the Federal Housing Finance Agency (FHFA) House Price Index (U.S. Federal Housing Finance Agency, All-Transactions House Price Index, retrieved from FRED, Federal Reserve Bank of St. Louis), and county-level housing-market trend data are sourced from the Federal Reserve Bank of St. Louis (FRED) — fred.stlouisfed.org — where available. This product uses FHFA data but is neither endorsed nor certified by FHFA.*","narrative":null,"meta":{"report_id":"r_229-n-whispering-hills-dr-naperville-il-60540","engine_version":"9c69d03","generated_at":"2026-11-12T14:34:38.236145Z","data_as_of":{"sales_through":"2026-09-09","assessment_year":2025,"tax_rate_year":null},"cache":{"hit":true,"age_seconds":210975,"key":"229-n-whispering-hills-dr-naperville-il-60540"},"cost_usd":{"data":null,"llm":null},"personas":[],"status":"complete","degraded_reason":null},"comps_omitted":"Comparable sales are not included in this public file. They are returned by the API (POST /v1/analyze), which is rate-limited and carries the data providers' required notices."}