How to build a prospecting list from a Google Maps search

A founder pulls 900 roofers out of Google Maps on a Sunday night, loads them into a sender, and by Wednesday the domain is on a warmup timeout and the reply folder is empty. The list was not the problem. Google Maps returned exactly what it was asked for. What the founder built was a phonebook, and phonebooks do not book meetings. This piece is about what has to happen between the export and the send to turn one into the other.

Why is Google Maps underrated for B2B?

For any business that serves a physical geography, Google Maps is the closest thing to a live directory of the real economy. Every listing has a name, category, address, phone, website, hours, review count, and often a photo of the storefront. That is more first party context than most paid databases will give you for a local operator.

The problem is that a raw export from Maps is a phonebook, not a prospect list. If you email 500 roofers with the same pitch you are doing telemarketing with extra steps. What turns a phonebook into a list is signal work.

Step 1: pick a tight market

A tight market is one vertical, one geography, one size band. Not "contractors in the Midwest". Something like "residential roofing companies in Peoria, Illinois with 5 to 40 employees". Tight enough that your email can reference something specific, wide enough that there are 60 to 200 companies to work.

For this article we will use residential roofing in Peoria as the running example.

Step 2: how do you pull the public data?

Search Maps for the vertical and city. Capture: business name, category, website, phone, address, review count, average rating, hours, and the Place ID. The Place ID is the stable key you want to dedupe on later.

Enrich each site with a quick crawl

Then crawl each website for a few extra fields: services offered, service area pages, staff or team page, careers page, any mention of financing partners, and the CMS or website builder in use. Every one of those becomes a possible signal.

Step 3: how do you apply buying signals?

Signals are the reason a specific business would buy from you this quarter. For roofing in Peoria, three that work: (a) hiring for a project manager (growth stress on scheduling), (b) financing partner listed (they sell bigger tickets), (c) website last redesigned before 2020 (they are already in a refresh mindset).

Cut ruthlessly by signal

Drop everything that does not carry at least one signal. It feels wasteful and it is not. A 40 company signal list will beat a 400 company blast every time.

Step 4: do they actually fit your delivery?

Fit is about you, not them. Do you actually want to serve a five person roofer? Can your onboarding handle a shop that answers the phone by first name? If you sell software with a $12k floor, cut anything under about 15 crews. Better to have 30 qualified than 300 blurred.

Step 5: how do you shape outreach around the signal?

One email, one signal, one ask. If the signal was the hiring page, the first line names it. If it was the financing partner, the first line names that. The pitch is the same but the entry point is not. This is where the work of curating a signal list finally pays off.

Milo runs this exact loop end to end: discover the businesses that match your signal, personalize the outreach, and send it from your own inbox. How Milo works.

Ethics note