The build-versus-buy conversation almost always starts as a cost question and almost never ends as one. A brand doing a couple of million on Amazon runs the numbers, sees a retainer sitting next to a salary, and concludes the salary is cheaper. On a spreadsheet it often is. The spreadsheet is also measuring the wrong thing.
Why the Salary Comparison Answers the Wrong Question
Comparing a retainer to a salary treats two very different commitments as though they were the same purchase. A salary is a fixed cost carried through every quarter, including the quiet ones, and it concentrates an entire marketplace operation inside one person’s knowledge. A retainer is variable and can be ended in thirty days. The right question is not which costs less this year, but which risk a brand is better equipped to carry.
The concentration risk is the one brand consistently underpriced. One in-house account manager means the advertising history, the supplier context, the case history with Seller Support, and the reasoning behind two years of decisions all live in one head. When that person leaves – and at this level of specialization, they do leave – none of it is written down. We have taken over accounts where nobody remaining at the company could explain what a campaign was for or why a particular ASIN had been suppressed.
There is also the cost nobody puts in the model: the months before a new hire is productive, the founder hours spent supervising work they cannot evaluate, and the recruitment cycle repeated when the first hire turns out to be wrong. None of that appears next to the salary line, and all of it is real.
The In-House Model Is Cheaper on Paper and Riskier in Practice
We are not arguing against building in-house. For plenty of brands it is clearly correct, and we say so when we see it. The model works when the operation is genuinely contained: one marketplace, a stable catalog, predictable seasonality, and a founder who understands the platform well enough to supervise the hire competently.
Where it breaks is supervision. A brand hiring its first Amazon manager is hiring for a skill set nobody internally possesses, which means nobody internally can judge the work. The failure mode is not incompetence – it is drift. The account keeps running, the reports keep arriving, revenue holds roughly steady, and it takes four quarters before anyone realizes the account has been maintained rather than grown. By then the competitive position has moved and the cost of catching up exceeds everything the salary saved.
The second break point is breadth. Amazon account management is not one job. It is advertising, listing content, inventory planning, account health, case management, brand protection, and increasingly a set of international considerations. One person can be genuinely excellent at three of those. They will be adequate at the rest, and the rest is where accounts get suspended.
Where Agencies Genuinely Fail to Justify a Retainer
It would be dishonest to write this without naming the other side. Plenty of brands have been badly served by agencies, and the pattern is consistent enough to describe precisely.
The first failure is the pooled junior. A brand signs on the strength of a senior conversation, and the day-to-day work lands with someone carrying fifteen accounts, none of them well. The second is the reporting substitute, where a monthly deck arrives full of metrics and empty of decisions, and the brand mistakes visibility for management. The third is scope drift, where the retainer covers advertising, the brand assumes it covers everything, and the listing content quietly rots for a year while both parties believe someone else owns it.
Any one of these makes the in-house hire the better option. The way to check before signing is uncomfortable but simple. Ask who specifically will touch the account each week. Ask what they will change, not what they will report. Ask what happens to the work when that person is out. Vague answers to those three questions are the entire diagnosis.
The Deciding Variable Is Complexity, Not Revenue
Revenue is the wrong axis, and it is the one every article on this subject uses. We have seen single-marketplace brands well past $5 million run beautifully with two in-house people, and brands a third of that size that genuinely needed outside help because they were selling across five marketplaces in four languages with a catalog that turned over every season.
The honest test is how many distinct competencies the operation demands at the same time. A single marketplace with forty stable SKUs demands perhaps three. The same revenue spread across the US, UK, Germany and Japan, with a seasonal product line and a compliance surface in every territory, demands closer to eight. No single hire covers eight, and no brand should expect one to.
The second test is what happens on a bad week. If the account is suspended on a Friday afternoon, who handles it? If a hijacker appears on the best-selling ASIN, how long before someone notices. If inventory misses the Q4 window, who saw it coming in September. A brand that cannot answer those three questions has a resourcing problem, and a job posting will not solve it.
How We Structure Marketplace Management for Brands at This Stage
When brands come to Sellers Umbrella for Amazon marketplace management services, the first thing we establish is which parts of the operation genuinely need us and which do not. We would rather run advertising and content while a brand keeps inventory planning in-house than pretend a full-service retainer is right for everyone. Our Revenue Core framework exists partly for this reason – it separates the parts of an account carrying profit from the parts carrying volume, and the answer frequently shows that a brand needs depth in two areas rather than coverage across nine.
Where we do take the whole operation, the structure matters more than the scope. Named people, not a pool. A weekly decision log rather than a monthly report, so the brand can see what changed and why it changed. And an explicit handover position from the start, because a brand that eventually builds its own team should be able to take the account back with its history intact rather than starting from nothing. An agency that makes itself impossible to leave is solving its own problem, not the client’s.
The build-versus-buy decision deserves better than a salary comparison. The real question is whether the operation’s complexity has outgrown what any one person can hold, and most brands know the answer before they open the spreadsheet – the numbers are usually assembled to justify a decision already made. If the account has been maintained rather than grown for two quarters in a row, that is the signal, whichever way it points. We are happy to tell a brand plainly when they should hire rather than retain us.
Author bio: Nirav Bhatt is the founder of Sellers Umbrella, an Amazon consulting agency that has managed over $200M in client revenue and scaled more than 100 brands across seven international markets. He writes about marketplace profitability, advertising architecture, and the operational side of scaling on Amazon. sellersumbrella.com
