Installer guide · 15 min read

Pay Per Lead vs Retainer vs Pay Per Appointment

Short answer: a retainer is a fixed monthly fee for an agency's time; pay per lead charges for each lead delivered; pay per appointment (or pay per meeting) charges for each qualified meeting booked or attended. With a pay-per-lead model you pay for results rather than time. At its strictest, the way TNW Marketing works, you only pay for qualified, booked commercial site meetings, so the agency carries the risk. With a retainer you pay a fixed monthly fee regardless of results. For most UK commercial solar installers, paying per qualified result gives a more predictable cost per meeting and less wasted spend. The catch is that “a lead” means very different things to different agencies, so the definition matters more than the label.

What pay per lead means

Pay per lead is a way of buying lead generation in which you pay the agency for each lead it delivers, instead of paying for its time. A retainer is the opposite: a fixed monthly fee for strategy, campaign management, outreach and reporting, whatever comes out of it. Between the two sit pay per qualified lead, pay per appointment and hybrid deals that combine a base fee with lead fees or bonuses. Sprintlaw’s guide to lead generation contracts lists all of these as common structures in UK agency agreements.

For commercial solar, where projects are fewer and larger and a wasted survey costs a surveyor’s whole day, the real question is who pays for the work between someone showing interest and your team standing on their roof.

What counts as “a lead”: the definitions matter more than the label

Two pay-per-lead companies can quote the same headline price and be selling completely different things. TTMC, a UK B2B telemarketing agency, notes that lead definitions and quality criteria “vary dramatically” from one business to the next, and that the key is a clear definition shared by everyone involved in qualifying. Sprintlaw puts the contract test simply: a lead should be defined in enough detail that both sides can tell whether a particular record qualifies for payment. In practice you will meet four levels:

Each step down that table moves work, and risk, from you to the provider, which is why the unit price rises as you go. For the checks a commercial solar lead should pass before anyone books a survey, see how to qualify commercial solar leads. To see which UK suppliers sell each level, on which pricing model and at what published price, read our commercial solar leads UK comparison of suppliers and prices.

Side-by-side comparison

Here is how TNW Marketing’s pay-per-lead model compares with a typical retainer agency:

Four pricing models compared, including who carries no-show risk

Most lead generation is sold in one of four ways. The column that matters most for commercial solar is no-show risk: a booked meeting where nobody turns up costs you a surveyor’s day, and someone has to pay for it.

Pay per appointment is the next step beyond pay per lead: rather than paying for a contact your team still has to convert into a meeting, you pay for the meeting. If that is what you actually want, read our guide to pay per appointment commercial solar leads, and check carefully whether a provider bills per booking or per attended meeting, because only the second moves no-show risk off you.

The honest downsides of pay per lead

Pay per lead is not automatically the safe option. The strongest case against it comes from TTMC, a UK telemarketing agency running B2B campaigns since 1990, in an article first published in 2016 called “Pay-per-lead: a penny wise, pound foolish approach?”. Its argument, in summary:

• Volume over quality. When an agency is paid per lead it is not paid for the time it takes to nurture complex, higher-value prospects, so it focuses on quick wins and risks handing leads to sales too early or before they are properly qualified.
• Costs move down the funnel. Your sales team then chases non-existent interest or prospects without the authority or budget to buy.
• Burnt data and reputation. Teams chasing quick successes tend to burn through data, and prospects contacted badly may not be worth contacting again.
• Strained relationships. If the lead target is unreachable because of poor data, a complex proposition or an unclear lead definition, trust between agency and client breaks down.

TTMC itself works to an hourly rate with a minimum engagement of 210 hours (six weeks at 35 hours a week) for lead generation, and says pay per lead has worked for its clients only in a few exceptional cases with short sales cycles and relatively low deal sizes. That is a fair view from an agency selling time, and worth weighing. Three more problems come up with pay-per-lead suppliers:

• Shared leads. Some suppliers sell the same enquiry to more than one installer. Sprintlaw’s advice is that exclusivity should never be assumed: if your business case depends on it, the contract needs to say so.
• Lead quality. A cheap lead that never answers the phone, or a tenant with no say over the roof, is not cheap.
• Disputes. Vague rejection rights tend to create invoice disputes rather than solve quality problems.

Notice that most of these problems disappear when the thing you pay for is a qualified, attended meeting with the decision-maker rather than a contact: an agency cannot get paid for a quick win that never turns up.

How to protect yourself

• Write the definition into the contract. Location, site type, ownership or landlord consent, energy spend, decision-maker, freshness and duplicates: whatever you need before you will send a surveyor.
• Get exclusivity in writing. Not just “exclusive”, but whether the lead can be resold and to whom. See exclusive vs shared solar leads for how to check it.
• Agree a replacement or credit policy. Sprintlaw recommends defining invalid leads clearly, with time limits, the evidence needed and whether credits or replacements are available.
• Avoid long lock-ins. Check the initial term and any minimum commitment. Sprintlaw suggests a three-month trial with a clear break right often works better for SMEs than a long lock-in.
• Ask for data and consent records. The ICO says it is not enough to accept a third party’s assurances that the information it supplies is compliant. Ask who compiled the data, how it was collected, what people were told and, for consented data, what records of consent exist. A reputable supplier should be able to show you.
• Measure the right number. Track cost per attended appointment and cost per signed project, not cost per lead. Our guide to what commercial solar leads really cost walks through the maths.

When a retainer is the better choice

Retainers can suit businesses that want broad brand marketing, or have an in-house sales team able to work large volumes of unqualified enquiries. They also make sense when you want an agency’s time for things a per-lead fee does not pay for: market research, cleaning and profiling your data, or long relationship building with senior buyers over a long sales cycle, which is TTMC’s case for paying per hour. If your goal is booked commercial surveys, paying per qualified meeting ties your spend directly to outcomes. If it is brand, website and inbound demand, read our guide to marketing agencies for solar installers first, and our renewable energy marketing agency page compares each kind of renewable energy marketing service on what you get for the money.

Questions to ask a pay-per-lead company

1. Exactly what do you charge for: an enquiry, a qualified lead, a booked meeting or an attended meeting?
2. What checks happen before a lead or booking reaches me, and can I see an example write-up?
3. Is every lead exclusive to me, and does the contract say so?
4. What happens if the prospect does not show, cancels or does not match the brief?
5. How do I reject a lead, how long do I have, and what evidence do you need?
6. Is there a retainer, set-up fee, minimum spend or minimum term?
7. Which channels do you use, and what data and consent records sit behind each lead?
8. Will I meet the decision-maker or bill payer, or just somebody who works there?

Our comparison of commercial solar lead generation companies applies these questions to UK pay-per-lead generation companies and agencies side by side, and the commercial solar lead generation guide covers the channels behind the leads.

A worked comparison (hypothetical numbers)

The figures below are round, made-up numbers to show the arithmetic. They are not anyone’s real prices, including ours. Imagine an installer who wants about seven commercial site surveys a month:

On paper the raw leads look cheapest per survey. But that figure leaves out the hours spent calling 50 enquiries, the shared ones another installer is already quoting, and the fact that the conversion rates are yours to hit: if your team books five rather than ten, the cost per survey roughly doubles. The retainer’s cost per survey swings with the agency’s month. Pay per attended appointment costs more per survey than the raw leads appear to, but the least in variance and team time. Run your own numbers in the lead calculator, working back from the installs you want each month, then turn each option into a cost per signed job with the solar cost per lead calculator.

How TNW Marketing’s pay-per-lead model works

TNW Marketing books pre-qualified, exclusive commercial solar site meetings with the decision-maker for UK installers, and is paid per qualified, attended appointment. In practice:

• Every prospect is checked for property ownership or landlord consent, energy spend, roof or land suitability and buying intent.
• Meetings go straight into your calendar and are exclusive to you.
• If a booking doesn’t meet the agreed brief, you don’t pay: bookings that cancel, don’t show or don’t match the brief are replaced or refunded.
• No retainer and no minimum spend.
• A show rate of 60%+.
• Prospects are found through outbound calling, email, LinkedIn and paid ads.

For how the calling and booking side works, see appointment setting for solar installers. To hear from installers who use it, watch the commercial solar installer case studies and client video reviews.