How we research our Back Bay guides

At a glance

Step 1: Find the questions people actually ask

Before a guide is planned, we look at what people search for about Back Bay and Boston brownstones, and how often, using keyword data from Ahrefs. A topic earns a page only when enough people ask about it. The biggest demand turned out to be citywide ("Boston brownstones"), so that page answers it from a Back Bay angle.

Studying the search results

For each guide we pull the results Google shows for its main search in Boston, with the questions in Google's "People also ask" box, and read the pages that rank highest: what they cover, how they are organized and where they leave the reader without an answer.

Setting the standard for each page

Those comparisons set a minimum for every guide: the subtopics it must cover, the questions it must answer and how deep it must go. A guide is not finished until it covers more of what the reader needs than the pages already ranking.

Step 2: Gather the data from the source

Every number on this site comes from a source that was opened and read, and that source is listed at the bottom of the page.

Government and official records

Tax rates and the residential exemption come from the City of Boston, deed excise and recording fees from the Suffolk County Registry of Deeds, loan limits from FHFA, and the rules of a sale (lead paint, the 6(d) certificate, smoke and carbon monoxide certificates) from the Massachusetts General Laws, the Boston Fire Department and the U.S. EPA. Rules for exterior work come from the Back Bay Architectural Commission.

Market data

Home values come from the Zillow Home Value Index, downloaded as monthly data for the Back Bay neighborhood, its ZIP codes and the City of Boston. Mortgage rates come from Freddie Mac's weekly survey. We use these figures exactly as published and name the month or week. Zillow publishes no street or building values, so we never invent one.

History and architecture

The history of each street and house type comes from the Back Bay Houses project, the Back Bay Architectural Commission and the Boston Groundwater Trust, which monitors the groundwater around the wood piles many houses stand on.

Step 3: How we use AI in our research

We use AI-assisted research tools for the heavy lifting: searching for sources, reading official documents and data files, pulling out the figures that matter and comparing them across sources.

Why we use it

Reading and cross-checking that much material by hand would take weeks for every guide. AI lets us go deeper: more sources per page, more figures checked against each other, and faster corrections when an official number changes.

What it does not decide

AI tools do not decide what is true. Every figure has to trace back to a source that was opened and is listed on the page. When a figure cannot be confirmed, it is left out, or the page tells you who to ask, such as the condo trust, the Commission or your lender.

Step 4: Check every figure

Research turns up disagreements between sources, and some widely repeated figures are wrong for Back Bay. Before a guide goes live, its key numbers are checked against the primary source.

Examples of what that checking caught

• The conforming loan limit. Many pages quote the national 2026 limit of $832,750. Suffolk County is a high-cost area, and its 2026 one-unit limit is $962,550, which we confirmed in FHFA's county file. See jumbo loans in Massachusetts.
• The most expensive ZIP code. ZIP 02199 has the highest Zillow value of the areas we track, but it covers the Prudential Center area, dominated by towers, so its values do not describe brownstones. See Back Bay ZIP codes.
• Brick or brownstone. Many Back Bay houses are red brick with brownstone trim rather than solid brownstone fronts, so we use "brownstone" in its everyday sense and say so. See what a brownstone is.

Automated checks on every page

Every page is also checked before it is published: that it lists its sources, that its language meets Fair Housing standards, that no two pages repeat each other, and that every link works.

Step 5: Review before publishing

Pages are reviewed by Susana Murphy, our recommended Back Bay agent, and each page shows the date it was last updated. When a page changes, the date changes with it. How we choose our recommended agents explains how we chose her.

The standards every page follows

• Fair Housing. Streets and buildings are described by their homes, lots, rules and costs, never by the people who live there.
• Yearly figures. Tax rates, loan limits and fees change every year, so each page names the year of the figures it uses, as in Boston's FY2026 tax rates.
• Not advice. The guides explain how taxes, loans and sales work. For your own situation, confirm with a Massachusetts attorney, CPA or lender.

Keeping the guides current

Zillow publishes new home values every month, Freddie Mac publishes mortgage rates every week, and Boston certifies its tax rates each December. We update pages when those figures change. The latest figures are on the Back Bay housing market page.

Spotted something wrong?

If a figure on any page looks out of date or wrong, send us a note with the page and the source you are looking at. We check every correction against the original source and update the page if it needs it.

Common questions