How do I choose a Google Ads agency for my ecommerce brand?

A homeware brand we audited last quarter had been through three agencies in eighteen months. Each pitch promised the same things (senior team, profit focus, transparency), and each ended the same way: junior account managers, blended ROAS reports, and a quiet plateau. The pattern is common because the questions buyers ask in the pitch rarely test the things that actually matter.

Specialism comes first. An agency that runs ecommerce, lead-gen, B2B SaaS and local services from the same pod cannot have deep instinct for feed structure, SKU economics or PMax cannibalisation. Ecommerce is its own discipline. If their case studies are mostly lead-gen, that is who they serve well, and you are not them.

Pricing model is the second filter. Percentage of spend rewards budget growth regardless of margin. Fixed monthly fee rewards results within a defined scope. Neither is automatically right, but the incentives are different and you should know which set you are signing up to.

Team seniority is the third. Find out who runs the account day-to-day, not who pitches. The pitch team and the delivery team are often different humans. Ask to meet the person whose Slack you will be on by week three.

Contract terms and the kill switch are the last two. Fixed minimum terms are fine when both sides have skin in the game, but you need a clean way out if results stall. A confident agency will tell you what they will do if month two and month three under-perform, not promise it will not happen.