Translated from the Japanese original on mureo.jp.
Ask an ad agency to run your ads and there is a management fee on top of the media spend. In the Japanese market the going rate is often cited as around 20% of ad spend, and the smaller you start, the heavier that burden feels. You hired them for strategy, and it feels like you are also paying for reporting and trafficking work. Plenty of advertisers seem to carry that feeling.
Whether the fee is high is determined less by the amount than by what you are paying for. Here we break down how the fee is set, and how costs change if you switch to in-house, flat-rate operations, or delegating to AI.
How the fee is set
The mainstream model applies a rate to your ad spend. Run JPY 1M a month at a 20% fee and that is JPY 200,000, rising in proportion to what you spend. Many agencies also set a minimum fee.
Under this arrangement, the smaller the budget, the heavier the rate. The effort of account design and daily checks does not change much between a JPY 100,000 budget and a JPY 1M one. Because that fixed effort is loaded onto a small budget, the minimum fee kicks in and the effective rate can exceed 30%. That structure is where small advertisers’ sense of being overcharged comes from.
Break the fee into its parts
Even at the same fee, what you get in return is not one thing. It divides broadly into three.
Deciding strategy Who you sell to, what, at what price. Which platforms to combine and how. This requires understanding the business and is not easily replaced. Of the fee, this is the part whose value is clearest.
Operational work Trafficking, adjusting bids and budgets, daily checks. Hands move, but most of it is routine and reducible to procedure. This is where in-housing and automation pay off most.
Producing reports Gathering numbers and packaging them into a document. It takes time, but it is not judgment itself. It is the part most suited to automation.
When a fee feels high, that feeling is usually aimed not at strategy but at the latter two: the work and the reporting. Separate them out and the direction for lowering costs becomes visible.
Three directions for lowering costs
Run it yourself (in-housing) The fee goes away, but the hours come back to you. If you hire, there is payroll. If you run the business on your own, check first whether what you gain in freed-up time is worth the time operations will take.
Switch to pricing that does not scale with spend Rather than a percentage of spend, this is taking on operations for a flat monthly amount. Costs do not jump as you raise budget, so it suits advertisers who intend to scale delivery. It also avoids the sense of being overcharged while amounts are small.
Hand the work and the reporting to AI Push routine work — trafficking, checks, reporting — onto AI, and put people on strategy and supervision. The cost of the work goes down and judgment stays with you. But delegate badly and a different cost appears.
What to verify before switching to AI ad ops
Delegating operations to AI speeds up the work, but speed alone is not reassuring. Delegate without handing over the criteria for judgment and the AI will look only at the surface of the numbers and quickly execute changes that look plausible. It can shift budget toward a product you do not want to grow purely because its CPA is low.
So before switching, verify two things. One: that you can hand over your business goals and priorities in writing up front. Two: that changes touching budgets or bids can require approval, and that a record remains so you can revert. With those two in place, you can delegate the work while keeping judgment.
The mureo tool we build is this shape as a product. Pricing is flat rather than a rate on ad spend; AI runs trafficking, checks, and reporting; and changes to budgets or bids go through human approval. You can use it to replace an agency with AI, or keep the agency and just make the substance visible. Risks and safety-side design when delegating to AI are in Is it safe to hand ad ops to Claude Code?, and what automation can actually do is in Can you automate ad ops with Claude Code?.
If, before the fee, what bothers you is not being able to read the reports, then Reading your agency’s ad report covers how to verify the substance while still delegating. If you are at the stage of looking for a provider, Outsourcing search ad management fits your situation.
Summary
Whether a fee is high is determined by its substance, not its amount. Under a rate proportional to spend plus a minimum fee, smaller budgets skew expensive. Split the fee into strategy, work, and reporting, and what you can lower is the work and the reporting. Whichever you choose — in-housing, moving to a flat rate, or delegating to AI — using “can I keep strategy and supervision in my own hands” as the criterion makes it easier to hold on to both cost and peace of mind.