Buying an existing boiler service company can save you two or three years of building a customer base from nothing. It can also mean paying for customers who have already left, or who will leave when the owner does. The difference is found in the details of the customer base, and those details are what this checklist is for.
First, the limits of this guide. It covers the customer base and the marketing assets from an operator's point of view. It is not a valuation method, legal due diligence or tax advice. Your adviser, lawyer and accountant handle price, structure and contracts. When you need help with the transaction itself, the group's business-sale brand, BizSell.ca, is the place to talk. If you are on the other side of the table and preparing to sell, our sister site Boilers.Business covers valuation drivers and exit readiness.
Step 1: Count active customers, not names
A ten-year-old boiler company's software may list thousands of customers. Many are one-time calls from years ago, people who moved, or duplicate entries.
Ask the seller for a report of customers with at least one paid visit in the last 24 months, and a second report for 24 to 48 months. Then look at the shape:
| Group | What it tells you |
|---|---|
| Paid visit in last 12 months | Your real working base |
| 12 to 24 months | Likely to call again if reminded |
| 24 to 48 months | Recoverable with effort |
| Older than 48 months | Treat as a marketing list, not goodwill |
A worked example. The database lists 2,000 customers. The reports show 520 with a visit in the last 12 months, 310 more in the 12 to 24 month band, and 450 in the 24 to 48 month band. Your working base is about 830 customers, not 2,000. That is still a valuable company; it is just a different conversation with your adviser.
Step 2: Read the agreement book line by line
The care-plan book is often the most valuable part of a small boiler company because it is recurring. Ask for:
- Every active plan, with start date, renewal date, price and what it covers.
- The renewal rate for each of the last three years.
- How renewals happen: automatic billing, an invoice, or the owner calling people.
- Any plans sold at a price the company can no longer afford to honour.
If renewals depend on the owner phoning each customer, assume some will lapse after the sale unless you replace that routine quickly. If several hundred plans renew in the same month, plan the staffing for that month before you close.
A worked example. There are 240 active plans, and the renewal rate has been 82%, 79% and 76% over three years. The trend matters more than the number. A falling rate suggests the visits have been rushed or the price has not kept pace, and you will need to fix the service before the marketing.
Step 3: Find out who the goodwill belongs to
In many small boiler companies, customers are loyal to a person rather than a brand. That is fine, but you need to know.
Read the last 100 online reviews. Count how many name the owner, how many name other technicians, and how many name the company. Ask the seller which commercial accounts, such as property managers and building owners, deal with them personally. Ask which technicians are staying, and whether key people have agreed to stay after closing.
If most reviews mention the owner by name and the owner is leaving on closing day, ask your adviser about a transition period during which the seller introduces you. That is a deal-structure question, not a marketing one, but the marketing evidence is what raises it.
Step 4: Check revenue concentration
List the 10 largest customers by revenue over the last two years. If they make up more than about a quarter of revenue, the company is exposed: one property manager changing suppliers can take a large share of the work with them.
For each large account, note who the contact is, whether there is a written service contract, when it ends, and whether it can be assigned to a new owner. Your lawyer should review any contract you are relying on.
Step 5: List every digital asset that must transfer
This is where buyers lose the most value without noticing. Make a list with three columns: the asset, who controls it today, and the transfer step.
- Domain name. Registered to whom, at which registrar, with which email address on the account.
- Website and hosting. Who has the login, who built it, and whether the content is owned outright.
- Phone numbers. The main number on the vans, website and listings. Confirm with the carrier that it can be ported to your account.
- Google Business Profile. Ownership, not just manager access, must move to you. Note the review count and rating at closing.
- Social accounts and ad accounts. Including payment methods and any remaining prepaid balances.
- Email and text lists. With the consent records. Canada's anti-spam legislation requires consent for commercial texts and emails, and ISED's CASL guidance says senders should be ready to prove it, so ask for the records before you message anyone.
- Customer database and software. Export rights, licence transfer, and historical service notes.
- Vehicle graphics and printed material. Not digital, but they carry the phone number and brand, so they belong on the list.
Step 6: Look at how the company is found today
Before you buy, search for the company's main services in each town it claims to serve, the way a homeowner would. Note where it appears in the map results and in the regular results. Look at which pages on its website bring in calls.
A company that only appears when people search for its name relies on existing customers and referrals. That is not a problem, but it means your growth will come from building new visibility, and the first-year marketing plan applies almost as if you were starting fresh.
The first 100 days after closing
The first three months decide whether the customers you paid for stay.
Days 1 to 10. Keep everything that customers recognise: the phone number, the listing, the website, the van graphics. Make sure calls are answered as before. Send existing care-plan customers a short, personal introduction from you, by mail or by message where you have consent.
Days 10 to 30. Call the top commercial accounts. Visit the biggest ones in person. Confirm the renewal dates in the agreement book and set up the reminder sequence in your name.
Days 30 to 60. Ask for reviews from every satisfied customer, so new reviews start to mention you and your team. Update the website's About page with the new ownership story, written plainly.
Days 60 to 100. Decide on branding. If you are changing the name, do it gradually, with "now part of" wording, and keep the old phone number. Begin the marketing that grows the base: the agreement offer to lapsed customers in the 12 to 48 month bands, and visibility in towns the company serves but does not appear in.
What to measure in year one
Three numbers tell you whether the transition worked:
- Agreement renewal rate compared with the seller's last three years.
- Calls to the inherited phone number month by month compared with the prior year.
- New reviews that name you or your team.
If renewals hold within about 10 points of the seller's history and calls are flat or rising, you have kept what you bought. From there, it is a growth question.
Checklist summary
- Active customers counted by recent paid visit
- Agreement book reviewed, with three years of renewal rates
- Goodwill tested through reviews and key accounts
- Revenue concentration in the top 10 accounts
- Every digital asset listed with a transfer step
- Current search visibility checked town by town
- A 100-day transition plan ready before closing
If you would like this done for you, see the buy-side review. For what comes after, read about relaunching an agreement book.
Frequently asked questions
What is the most common mistake buyers make?
Treating every name in the customer database as an active customer. Count only customers with a paid visit in a recent window, such as the last 24 months, and look separately at active care plans.
Should I rename the company after I buy it?
Not on day one. A sudden new name can look like the old company closed. Most buyers do better with a gradual transition, such as 'now part of' wording for a period, while customers get to know them.
Who should value the business?
A qualified adviser, not a marketing firm. For business sales and valuations, the group's brand is BizSell.ca. Your lawyer and accountant handle the contract and tax structure.
What digital assets must transfer?
At minimum the domain, website hosting, phone numbers, Google Business Profile, social accounts, ad accounts, email lists with their consent records, and the customer database. Each one needs a named owner and a transfer step in the closing checklist.
Sources
- ISED: Getting consent to send email (CASL) (2026-10-23)