Find your first customers

Where do I find my first 100 people? Describe your customer in one sentence: your agent counts the market, lists the companies that fit with evidence, and finds the person at each.

Find your first customers

You, to your agent

Find property managers with 20 to 400 units who still run rent on spreadsheets.

Show me the first 25, and the person to email at each.

curl -X POST https://api.sb/leaseline.app/icps \
  -H "Authorization: Bearer $STARTUP_BUILDER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"description":"US property managers with 20 to 400 units still running rent on spreadsheets"}'

# Not live yet (gaps #11)
curl -X POST https://api.sb/leaseline.app/organizations/count \
  -H "Authorization: Bearer $STARTUP_BUILDER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"icp":"icps/icp_3"}'

# Not live yet (gaps #2)
curl -X POST https://api.sb/leaseline.app/prospects/find \
  -H "Authorization: Bearer $STARTUP_BUILDER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"icp":"icps/icp_3","question":"Do they still track rent in spreadsheets?","save":25}'

# Not live yet (gaps #11)
curl -X POST https://api.sb/leaseline.app/prospects/prospects%2Fprospect_118/verify \
  -H "Authorization: Bearer $STARTUP_BUILDER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"maxCost":0.03}'

 1import { $ } from 'startup-builder'
 2
 3const icp = await $.ICP.create({ description: 'US property managers with 20 to 400 units still running rent on spreadsheets' })   // your customer, in one sentence
 4await $.Organization.count({ icp })   // free: how many companies match · Not live yet, gaps #11
 5const rows = await $.Prospect.find({ icp, question: 'Do they still track rent in spreadsheets?', save: 25 })   // fit with evidence, why now, the person · Not live yet, gaps #2
 6return await $.Prospect.verify({ prospect: rows.matches[0], maxCost: 0.03 })   // the work email, checked, only for rows you approve · Not live yet, gaps #11

npx startup-builder do ICP.create --json '{"description":"US property managers with 20 to 400 units still running rent on spreadsheets"}'
npx startup-builder do Organization.count --json '{"icp":"icps/icp_3"}'   # Not live yet (gaps #11)
npx startup-builder do Prospect.find --json '{"icp":"icps/icp_3","question":"Do they still track rent in spreadsheets?","save":25}'   # Not live yet (gaps #2)
npx startup-builder do Prospect.verify --json '{"prospect":"prospects/prospect_118","maxCost":0.03}'   # Not live yet (gaps #11)

{
  "name": "do",
  "arguments": {
    "code": "const icp = await $.ICP.create({ description: 'US property managers with 20 to 400 units still running rent on spreadsheets' })   // your customer, in one sentence\nawait $.Organization.count({ icp })   // free: how many companies match · Not live yet, gaps #11\nconst rows = await $.Prospect.find({ icp, question: 'Do they still track rent in spreadsheets?', save: 25 })   // fit with evidence, why now, the person · Not live yet, gaps #2\nreturn await $.Prospect.verify({ prospect: rows.matches[0], maxCost: 0.03 })   // the work email, checked, only for rows you approve · Not live yet, gaps #11"
  }
}

Response200application/json

 1{
 2  "$type": "ProspectList",
 3  "count": 4180,
 4  "matches": [
 5    {
 6      "organization": "Northgate Rentals",
 7      "units": 140,
 8      "fit": "strong",
 9      "evidence": "We still collect rent by check and track it in a spreadsheet (northgaterentals.com/about)",
10      "whyNow": "posted a leasing coordinator role on 2026-10-21",
11      "person": "Owner",
12      "email": "verified"
13    },
14    {
15  …

sample · 3 Not live yet

Count free, 25 rows about 5¢, 100 checked emails about $2: about $2
First run: Partly works today
Status: API
Runs by: nothing
Connect once

What you get

Field	What it says
Fit	Strong, possible or no, from one question your agent asks of each company’s own site.
Evidence	The words on their site the fit rests on, quoted with the page.
Why now	The latest dated event: funding, a hire, a new tool, a complaint about a rival or a question in public.
Person	The decision maker’s name and title. Names and titles cost nothing.
Work email	Found and checked only for the rows you approve. A blank reads unknown, never zero.
First line	An opening line that quotes the evidence or the reason to reach out now.
Cost	The most the list can cost, shown before it runs, and what it cost after.

Jobs inside it

Job	What it returns	Price	Status	Runs by
Market size	How many companies match your customer, by size and place	free	Coming	API
Describe your customer	Companies or people that match a plain sentence, by meaning	$0.007 for 10 rows	Coming	API
People list	Names and titles at the companies that fit, with whether an email exists	free	Works today	API
Work email	The person’s work address, checked in the same call	1 to 3¢ a found address; misses are free	Works today	API
Email check	Valid, catch-all or invalid, before the first send	$0.00178 an address	Works today	API
Lookalikes	More companies like your best one, each with the reason it matched	$0.04 a row	Coming	API
Decision makers	Who to talk to at a named account, ranked by role	$0.0005 a row	Coming	API
Who just raised	Companies that announced funding, with the round and the date	$0.04 a row	Coming	API
Who is hiring for the job you do	Companies with an open role your product replaces or helps	$0.0005 a row	Coming	API
Post engagers	People who reacted to or commented on a post in your category	$0.003 a post	Coming	API
Company and person profiles	Size, industry, tech stack and role for every row you keep	about $0.002 a row	Coming	API
Who is visiting	The companies behind the visits to your site today	a fraction of a cent a visit	Coming	API
Saved lists	The approved rows as one saved list that refreshes weekly and feeds email, LinkedIn and ads	free	Coming	API

Where and how it runs

Where it works	How it runs	Connect once
LinkedIn, Reddit, X, GitHub	API	nothing

Your agent acts as you on every Venue you authorize. Where a Venue has no API, a browser agent signs in as you and does the steps.

Plays that use it

Play	Strategy that runs it
Cold email	Hands-on
LinkedIn outbound	Hands-on
Paid social	Hands-on
Buying committee	Hands-on

Reference

Tool	Runs today
`Prospect.find` (Not live yet, gaps #2)	Coming
`Organization.count` (Not live yet, gaps #11)	Coming
`Organization.find` (Not live yet, gaps #11)	Coming
`Prospect.verify` (Not live yet, gaps #11)	Coming
`POST /{namespace}/icps`	Coming

Compiled, not written: edit the records it reads (catalog/find-customers), then regenerate. Every step runs from a sentence or a line of code. In your words: the CRM words you know, and where each lives here.

What you getCopy Anchor Link

Jobs inside itCopy Anchor Link

Where and how it runsCopy Anchor Link

Plays that use itCopy Anchor Link

ReferenceCopy Anchor Link

Contents

What you get

Jobs inside it

Where and how it runs

Plays that use it

Reference