How we research Main Line homes

This site, counted

How a guide gets made

1. Find the questions people askWe start from what people search before buying or selling on the Philadelphia Main Line: keyword research across the whole topic, then the pages that rank and the questions Google shows for every page we write.
2. Go to the original sourceProperty tax rates come from Montgomery, Delaware and Chester counties and each school district; tax rules from the Pennsylvania Department of Revenue, the IRS and the City of Philadelphia; loan limits from FHFA; home values from Zillow's Home Value Index; housing stock from the Census Bureau; mortgage rates from Freddie Mac; train times from SEPTA; school information from each district and school; and crime figures from township police departments, Pennsylvania and the FBI.
3. How we use AIWe use AI-assisted research tools to find, read, extract and cross-check sources, because they let us check far more documents than research by hand could. AI does not decide what we publish: every figure traces to a source listed on its page, and a figure we can't confirm is left out or turned into a check for you to run.
4. Check every figureEach number is checked against its source, and every example is recalculated, before a page goes live. A second editor then reads each page against the sources. Errors caught that way on this site before launch:
   • A private school draft gave a 13-year tuition share of 32% to 37%. Recalculated across every school in its table, the range is 17% to 37%.
   • A Delaware County sheet still showed 2025-26 school tax rates. The tax pages now use each district's own 2026-27 rate, which moved Radnor's total to 23.6454 mills.
   • A Villanova draft gave a distance to Center City without saying where it was measured from. It's measured from the station, and the page now says so.
   • A guide to Wayne assumed its ZIP reached Easttown. By Census land area, 19087 is Tredyffrin, Radnor and Upper Merion.
5. Reid's reviewReid Rosenthal reviews every page before it goes live. Each guide shows the date he last reviewed it.

The standards we hold to

We describe places by their homes, prices, taxes and amenities, never by who lives there, as the Fair Housing Act requires. Wealth questions are answered with home values only. For schools we name the district and link its own address lookup, rather than tying a home to a school. Safety pages use official data and explain the method, without a safe or unsafe verdict. Figures are dated, and nothing on this site is tax, legal or lending advice.

See it in practice in the Main Line property tax guide, the Main Line school districts guide and the Main Line crime data guide.

Keeping pages current

Tax rates are rechecked when counties, townships and school districts adopt new rates each year; loan limits when FHFA publishes them; Zillow market figures when Zillow publishes new monthly data. Each page shows the date Reid last reviewed it, from the Main Line homes page down.

Corrections

Spotted something wrong? Email reid.rosenthal@foxroach.com and we'll fix it and note the change.

Common questions

Sources

• Zillow Research: housing data
• Freddie Mac: Primary Mortgage Market Survey
• FHFA: conforming loan limits
• Pennsylvania Department of Revenue
• US Census Bureau: American Community Survey