How to Find and Vet a PPC Agency That Actually Delivers ROAS
The hiring checklist, red flags, and honest questions that separate high-performing PPC agencies from retainer collectors.
Hiring a PPC agency is one of the highest-stakes vendor decisions a growth team makes. Get it right and paid search compounds your other marketing investments. Get it wrong and you're six months into a retainer with a deteriorating ROAS and an account you can't easily migrate. This guide gives you the framework to choose well the first time.
Through The Glass Creatives manages paid media as part of integrated growth programmes. We've also inherited accounts from agencies that - on paper - looked excellent. What a closer look inside revealed is why this guide exists.
Before reading this, it helps to understand what PPC management services actually include and what PPC management costs at different service tiers, so you know what you're evaluating.
The Qualifying Questions Every PPC Agency Should Answer
Who is the specific person managing my account, and what's their experience level and current account load?
Walk me through a campaign you've optimised in my vertical - what was the problem, what did you change, and what was the result?
What testing framework do you use, and how long before we'd expect to see statistically meaningful results?
How do you handle attribution in a funnel that includes offline conversions or a long sales cycle?
What happens to the account and data if we end the engagement?
Red Flags That Are Almost Always Disqualifying
They cannot name the account manager you'd work with before you sign
Their "guarantee" involves traffic volume, not revenue or cost-per-acquisition
They resist sharing account access or owning your account under your MCC
Case studies only show CTR improvements, not ROAS, CPA, or revenue impact
They pitch exclusively on bid automation - without a creative or landing page strategy
What Good Onboarding Looks Like
A high-calibre PPC agency starts with a thorough account audit (if inheriting) or a structured discovery sprint (if building from scratch). They establish conversion tracking before spending a dollar on live campaigns. They document the account structure and share it with you. They set realistic ramp expectations - most accounts need 60-90 days before performance stabilises after structural changes.
Choose TTGC if / Choose a PPC Specialist if
Choose TTGC if you need paid media integrated with brand strategy, SEO, and CRO - channels that compound one another. Choose a dedicated PPC-only agency if your growth plan is 100% paid acquisition at high volume and you need a team with ten years of platform-specific depth.
"The best PPC agencies treat your budget like it's their own money. They ask uncomfortable questions about margins and LTV before they write a single headline." - Mherie Vic Prevendido, TTGC
Sources
- Clutch - "How to Evaluate a Digital Marketing Agency." Clutch.co, 2025.
- Google - "Google Partner Requirements & Benefits." Google Ads, 2026.
- Search Engine Land - "PPC Agency Vetting Checklist." Search Engine Land, 2025.
- Databox - "How Long Does PPC Take to Work?" Databox, 2025.
Talk to TTGC about your paid media goals - no retainer commitment required for the first call.
Book a free Brand and Growth Assessment and see exactly how Through The Glass Creatives would approach it.
