Data and Methodology
Every figure published on Warren, Local. comes from Garden State MLS records for Warren Township, checked against Somerset County parcel records. This page explains how that database is built, how the numbers are computed, what gets excluded, and what this publication refuses to print. It exists so you can check the work.
The database
The database holds 4,812 closed Warren Township sales carrying a sale price, the earliest closing February 6, 1997 and the most recent September 4, 2026, as of the September 6, 2026 refresh. Records come from the Garden State MLS and are joined to the county tax and parcel file. Duplicate and superseded listings are excluded. Closings report to the MLS with a lag, so recent weeks fill in over time, and a figure computed today can differ from the same figure computed a month from now. When that moves a published number materially, the page is corrected and says so.
NOTE: This representation is based in whole or in part on data supplied by the Garden State Multiple Listing Service, L.L.C. ("GSMLS"). GSMLS does not guarantee nor is in any way responsible for its accuracy. Data maintained by GSMLS may not reflect all real estate activity in the market.
Two dates, two meanings
Pages on this site carry two different dates and they are not the same. The most recent closing is the last sale the database has recorded. Updated is when the page was last rebuilt. A page updated today can honestly carry a most recent closing from two weeks ago, because that is simply the last sale that has reported.
What counts as a sale
Sale figures cover every residential property type sold through the MLS in Warren Township, including townhouses and condominiums, not detached houses alone. Attached product sells below detached in Warren, so a detached only median would run higher, and pages say so where it matters. One page applies a stricter floor: Selling in Warren excludes sales under $200,000 as likely non arms length, which is why its counts run slightly below the same windows elsewhere on the site. Each page states the basis it uses.
How the statistics are computed
Medians are computed exactly, never approximated, because an approximate median can drift between runs and put two different numbers on two pages for the same window. Year over year comparisons hold the window fixed: January 1 through the same month and day in both years. Monthly figures in a town that closes 10 to 25 sales a month swing hard on small samples, so monthly posts say what a month cannot tell you and the trailing twelve month figures carry the conclusions.
Price per square foot, three bases
Price per square foot appears on this site on three bases, and each figure is labelled where it appears.
The strict basis divides the sale price by the living area in the county parcel record and exists only where a parcel match exists. It is the most conservative figure and covers the fewest sales.
The broader basis takes the parcel record where it exists and the listing's own square footage where it does not, which roughly half again as many sales can support.
The Warren Housing Index (WRNX) uses the broader basis inside its own window, with two filters: price per square foot outside $50 to $1,500 is treated as a data error, and records under 400 square feet are excluded. The index is the median closed price per square foot, indexed so that calendar year 2000 equals 100. It is not inflation adjusted and it is not a forecast.
Three bases produce three defensible numbers for the same market. None is wrong. What would be wrong is quoting one without saying which it is.
Known limits, stated plainly
County parcel coverage is partial on recent sales and gets thinner the closer to today you look, because the newest closings have not yet been matched to the county file. Tables built on parcel fields are scoped to the matched records and say so.
Attached homes are excluded from lot size comparisons. The listing field for a townhouse often carries the whole association's acreage while the county record carries a tiny per unit footprint. The two sources distort in opposite directions, so neither belongs next to detached houses.
Tax bills on new construction are not published as medians. The assessment on record often predates the house, which makes the figure meaningless for a buyer.
What this publication will not print
No unverified fact. No invented figure, date, name or quote. No asking price or opinion of value for an individual address, aggregate statistics only. No superlative beyond what the record supports. When a source cannot be read or a figure cannot be verified, the item is omitted or the gap is stated, and several pages carry a "what I could not verify" note for exactly that reason.
Corrections
If a number here ever disagrees with a Township, county or district document, the document governs and this site is wrong. Corrections are dated and stay on the page. Dated monthly posts are left as published and carry a note stating the current figures, because rewriting an archive quietly is worse than being wrong loudly. When a headline itself carried a figure that changed, the headline is corrected and the note says so.
Independence and offers
Warren, Local. is written by John Mangini, broker of record at NextHome Premier, which sells real estate in Warren. Reporting here is not conditioned on that. Market pages carry a clearly marked offer for a property specific analysis. Civic, school and community coverage carries none.
- Garden State MLS closed sales for Warren Township, joined to Somerset County tax and parcel records.
- Township of Warren, Somerset County and school district documents, cited on the page that uses them.
- US Census Bureau, QuickFacts and American Community Survey, for population and demographic figures.
- Federal sources named on the page for national data: Freddie Mac, FHFA, NAR, Census and HUD.
Updated September 14, 2026. When a computation standard on this page changes, the change is noted here rather than made silently.
Warren Township resident and full time broker, licensed in New Jersey since 2002. Warren, Local. is written from live Garden State MLS data, township records and primary sources. Every figure is traceable to a source listed above.