The Ultimate Guide To Vetting UK Google Ads Experts

I see this all the time. A UK SaaS founder, sharp as a tack, has built a brilliant product but is getting absolutely rinsed on Google Ads. They hire a generic PPC agency that promises the world, spends thousands of pounds on clicks, generates a handful of rubbish leads from the wrong kind of companies, and then shrugs when the founder asks where the ROI is. The problem isn't Google Ads. The problem is you're hiring the wrong people to run it.

B2B SaaS isn't like selling shoes or booking cleaning services. The sales cycles are long, the decision-making units are complex, and the person searching on Google might not even be the one who signs the cheque. Most agencies don't get this. They apply a B2C mindset to a B2B problem and burn your cash in the process. You need a partner who thinks less like an ad manager and more like a CFO with a marketing budget. This guide is about how to find that partner in the UK, without getting burned.

So, why is B2B SaaS so different on Google Ads?

Before we even get into vetting agencies, you need to understand why your business is a unique challenge. If you don't grasp this, you can't ask the right questions. The average PPC agency thinks success is a low Cost Per Click (CPC) and a high Click-Through Rate (CTR). For you, those are vanity metrics. They mean nothing.

Your world is about Customer Acquisition Cost (CAC) and Lifetime Value (LTV). You might have a CAC of £2,000, which would give a B2C ecommerce manager a heart attack. But if your LTV is £20,000, that's a brilliant investment. Your sales cycle might be six months. The person who downloads your whitepaper today might not become a customer until next year. It's a long, complicated journey that requires a completly different strategic approach.

Most agencies are built for speed and volume. They want quick wins to justify their retainer. They'll target broad, top-of-funnel keywords because they're cheaper, get you lots of clicks, and make their monthly report look good. But those clicks are from tyre-kickers, students, and competitors. Not from the Head of Engineering at a 100-person tech company who has the exact, expensive problem your software solves. Finding that person, with that specific commercial intent, is the whole game. And that requires a level of precision and business acumen that most agencies simply don't have. If you're looking for a deep dive on this, our guide to B2B Google Ads in the UK covers this ground in more detail.

The Vetting Framework: How to Spot a Genuine Expert

Alright, so how do you separate the experts from the cowboys? You need a systematic approach. It’s not about their fancy office in Shoreditch or the awards on their shelf. It's about whether they demonstrate a deep, almost obsessive, understanding of your business model. This isn't just about hiring a service; it's about finding a growth partner.

1. Case Studies Are Your First and Most Brutal Filter

This is non-negotiable. Before you even agree to a call, you must see evidence that they have successfully run Google Ads for other B2B SaaS companies. Not B2B services. Not high-ticket ecommerce. Specifically B2B SaaS.

What to look for:

• -> The Right Metrics: Do they talk about ROI and ROAS? Great, but for SaaS, the real gold is in metrics like Cost Per Trial, Cost Per Demo, or Cost Per Acquisition (CPA). We had one client, a medical job matching platform, where we took their CPA from a painful £100 down to just £7. That’s the kind of result that matters. It shows an understanding of the entire funnel, not just the ad click.
• -> Niche Similarity: Have they worked with companies at a similar stage to yours? A strategy for a seed-stage startup trying to find product-market fit is vastly different from one for a Series B company looking to scale aggressively.
• -> Transparency: Do they explain the 'how' and 'why' behind the results, or is it just a bunch of impressive-sounding numbers? A good case study should tell a story about the problem, the strategy they implemented, and the tangible business outcome. Avoid anyone who is cagey about the details.

If an agency can't show you at least 2-3 detailed case studies that look and feel like your business, thank them for their time and move on. You are not paying them to learn on your dime. This is the core of the framework for vetting UK Google Ads experts – proof, not promises.

2. The Discovery Call is An Audit, Not a Sales Pitch

The first proper conversation you have with a potential partner is the most telling part of the process. You can tell within 20 minutes if they're the real deal. A bad agency will spend 90% of the time talking about themselves, their process, their team, and their 'proprietary technology'.

A true expert will turn the tables and audit you. They should be asking you tough, insightful questions like:

• "What's your customer LTV? And how do you calculate it?"
• "What's your monthly churn rate?"
• "What's your sales conversion rate from a demo to a paying customer?"
• "Who is your Ideal Customer Profile? Not their job title, but what is the 'nightmare' problem that keeps them up at night that you solve?"
• "What does your onboarding process look like for new trial users?"

If they aren't asking these questions, they cannot possibly build a successful strategy for you because they don't have the basic inputs. They are planning to treat your account like any other, which is a recipe for disaster. The goal of this call shouldn't be for them to sell you, but for you both to figure out if there's a good fit. It’s why we offer a free strategy session where we go through a potential client’s account and strategy—it’s the only way to know if we can actually help.

3. Do They Understand the Maths? The LTV:CAC Equation

This is where the amateurs are exposed. A great B2B SaaS ad partner must be comfortable talking about unit economics. They need to understand that your goal isn't cheap leads; it's acquiring customers at a cost that is sustainable and profitable over the long term. The magic ratio is LTV to CAC. A healthy SaaS business typically aims for an LTV:CAC ratio of 3:1 or higher. This means for every £1 you spend to acquire a customer, you get at least £3 back in lifetime value.

Your potential partner should be able to have this conversation with you. They should be helping you work out how much you *can afford* to pay for a lead, based on your business metrics. If they just ask "what's your budget?" without this context, they're just thinking about how to spend your money, not how to invest it.

Use this calculator below to get a handle on your own numbers before you even speak to an agency. If you walk into the conversation knowing your LTV, you're already in a much stronger position.

4. The Offer is More Important Than The Ads

This is a big one, and a real sign of a top-tier partner. They will scrutinise your offer. The single biggest reason B2B ad campaigns fail is a high-friction, low-value Call to Action. The classic "Request a Demo" is often a conversion killer. It asks for a huge commitment (30-60 minutes of someone's time) in exchange for an unknown value (a sales pitch).

A great agency will challenge this. They'll push you to think about Product-Led Growth. Can you offer a free trial? A freemium plan? If not, what's the next best thing? A valuable, free tool? An automated audit? A piece of content that genuinely solves a small part of their problem right now? They know that their ads can only be as good as the destination they're sending traffic to. If they don't mention your landing page and your offer within the first call, that's a massive red flag. They should be as interested in your conversion rate as they are in their click-through rate.

Visualising the Vetting Process

It can be a lot to take in. To make it simpler, here is a flowchart that maps out the ideal process for finding and hiring the right Google Ads partner for your SaaS business. Follow these steps, and you'll dramatically reduce your chances of making a costly mistake.

Red Flags: When to Run for the Hills

Just as important as knowing what to look for is knowing what to avoid. The UK market, especially around London's tech scene, is full of agencies that talk a good game. Here are the warning signs that should have you backing away slowly.

• Guaranteed Results: This is the biggest red flag of all. No one can guarantee results in paid advertising. There are too many variables. Anyone who promises you a specific ROAS or number of leads is either lying or inexperienced. An expert will talk in terms of a structured testing plan and data-driven optimisation.
• Long, Inflexible Contracts: A common tactic is to lock you into a 12-month contract. A confident agency will often be happy with a 3-month initial term or even a rolling 30-day contract after a trial period. They should be confident enough in their ability to deliver value that they don't need to trap you.
• Vague Reporting: If their sample report is full of fluffy metrics like 'impressions', 'reach', and 'clicks', be very wary. You want a report that focuses on what matters: leads, trials, demos, cost per acquisition, and ultimately, revenue. It should connect their activity directly to your business goals.
• Lack of Transparency: Who owns the Google Ads account? The answer must always be YOU. If the agency insists on creating it under their own manager account and won't give you full admin access, walk away. You're building a valuable data asset, and you must own it.
• The Reference Request Dilemma: This is a slightly contrarian one. If you've seen detailed case studies, had an in-depth strategy call, and you're happy with the proposal, asking to speak to one of their current clients can actually be a red flag for the agency. It signals a fundamental lack of trust from the get-go. Tbh, if a prospect gets to that stage with us and still needs to talk to a client, we usually figure we're not a good fit. All the proof should already be on the table.

Agency vs. Consultant in the UK SaaS Scene

You'll come across different types of partners, and it's worth knowing the difference. For a SaaS business in the UK, especially in a hub like London or Manchester, you have plenty of choices.

Agencies: They have a full team (strategists, account managers, copywriters, designers). They can often move faster and have broader capabilities. The downside is you might get a more junior person managing your account day-to-day. When vetting an agency, it's absolutley critical to know who, specifically, will be working on your account. The expertise of their senior team means nothing if your account is handled by an intern. This is a crucial question to ask when you're looking for the right Google Ads expert in London.

Consultants/Freelancers: Here you're hiring a specific person. You get their direct expertise and attention, which can be fantastic. The potential drawback is that they are a single point of failure and may have less capacity. A good consultant often has a strong network of other specialists they can bring in if needed.

There's no right or wrong answer here. It depends on your needs, budget, and how hands-on you want to be. The vetting framework remains exactly the same for both. Don't be swayed by the size of their team; focus purely on their demonstrated B2B SaaS expertise. Sometimes, the choice between a consultant or an agency in London comes down to the specific individual you'll be working with.

The Final Check: What You Need to Bring to the Table

Remember, this is a partnership. Even the best agency in the world can't succeed if the foundations aren't there on your side. Before you sign a contract, make sure you're ready.

1. You have a solid product: Advertising can't fix a bad product. If you have high churn and poor user feedback, spend your money on product development first.
2. You know your numbers: You must have a grasp of your LTV and conversion rates. If you don't, you can't set realistic goals or budgets.
3. You have a clear ICP: The agency will help you refine this, but you need to come to the table with a clear idea of who your best customers are.
4. You're patient: It can take 2-3 months to get a B2B SaaS campaign properly dialled in. You need to give the process time to work and not panic after a week of low lead volume.

Your Action Plan for Hiring the Right Partner

You now have a complete framework for making a smart, informed decision. It's not about finding the cheapest option or the one with the slickest sales deck. It's about finding a true partner who understands the unique economics of your B2B SaaS business and has a proven track record of helping companies like yours grow profitably.

This is the main advice I have for you:

Executing this level of due diligence takes time, but it's nothing compared to the time and money you'll waste with the wrong partner. Getting paid acquisition right can be the single most powerful growth lever for your SaaS business, but only if it's wielded by an expert who understands your world.

If you're going through this process and want a second opinion, or want to see what an expert-led B2B SaaS strategy could look like for your business, we offer a completely free, no-obligation strategy session. We'll audit your current efforts (or plans) and give you actionable advice you can use, whether you decide to work with us or not. Feel free to get in touch to schedule your free consultation.