Choosing a CSS partner
Every certified CSS gives you the same auction terms, because a regulator requires it. The comparison is therefore not about the discount at all. It is about what the partner charges, what else they do with your account, and whether you can leave.
What is identical
The auction. A product bid through any certified CSS competes on the same terms as through any other, and as through Google Shopping Europe. A partner claiming a larger discount than the rest is describing the same mechanism with different arithmetic, or describing something that is not the CSS advantage.
What differs
| What to compare | Why it matters |
|---|---|
| Pricing model | Flat fee, percentage of spend, or a share of the saving |
| Who manages campaigns | Self-service, or the partner takes over your Ads account |
| Country coverage | Whether every market you advertise in is served |
| Partner tier | Premium partners meet higher volume and compliance standards |
| Multi-account tooling | Decisive for agencies, irrelevant for one shop |
| Exit terms | Notice period, contract length, who owns the association |
The pricing model matters more than the price
A flat monthly fee and a percentage of spend look similar at one spend level and diverge sharply at another. A percentage model costs more precisely as you succeed, and it means your CSS earns more when your CPCs rise. A flat fee, such as the 24 euro a month Cobiro charges, is the same at 500 euro of spend and at 50,000, so the saving accrues entirely to you as you grow.
Be careful with "we take a share of what you save". It sounds aligned, and it requires agreeing on a counterfactual, namely what you would otherwise have spent, which is unmeasurable after the fact.
Managed or self-service
Some CSS partners require that they manage your Google Ads campaigns as a condition of the CSS relationship. That can be the right arrangement, but it is a different purchase: you are buying agency services with a CSS attached, not a CSS. Cobiro is self-service and does not touch your campaigns, which suits merchants and agencies who already have the expertise in-house.
The questions worth asking
- Is the fee flat, and does it change with my spend?
- Do you need access to my Google Ads account, and why?
- Which of the countries I advertise in are covered?
- What is the notice period, and what happens to my Merchant Center if I leave?
- Is there a trial long enough to measure the effect in my own account?