By Ted Gibson — RippleEffect
For most UK brands the comparison is not close, and the fee is not the reason. Build Grow Scale puts the point where building in-house becomes economically justifiable at $15m to $20m in annual Amazon revenue, which is far above where most brands asking the question actually sit. The difficulty below that line is not that good people are expensive. It is that one hire cannot cover the job, and the salary that buys real seniority costs more than the channel can carry.
What an Amazon hire actually costs in the UK
Pare scraped 416 Amazon PPC job postings from LinkedIn and puts London on-site salaries at £45,000 to £55,000 and London hybrid at £60,000 to £65,000, refreshed in August 2026. Salary is not the cost, though. Employer National Insurance adds 13.8% above the threshold, and Build Grow Scale's rule of thumb is to multiply the salary by 1.25 to 1.35 and add $1,500 to $6,000 a year for tools. Pare's own fully loaded figures land at $65,000 to $80,000 for a London on-site hire and $88,000 to $100,000 for hybrid. The equivalent hire in New York runs $125,000 to $162,000.
Then there is everything one person does not cover. Build Grow Scale reckons a properly resourced internal team, spanning advertising, catalogue, inventory operations and compliance, costs $200,000 to $350,000 in salaries alone, before benefits, tools, recruitment and the time someone spends managing them. The hire can also fail, and Pare puts the cost of a bad one at 50% to 200% of annual salary. A brand doing £50,000 a month is being asked to carry that risk on a channel where a single person stands between it and a stockout.
Where the freelancer option breaks
A freelancer is the cheapest hour you can buy and often the right answer for a defined piece of work, a listing rebuild or a launch. What the day rate does not buy is cover. One person on holiday, off ill, or quietly taking on a better client is the whole of your Amazon capability. We could not find a published UK day rate benchmark for Amazon specialists that discloses its method, which is worth knowing in itself: you will be negotiating without a reference price, against someone who knows exactly what they charged last time.
Put the agency fee in salary terms
Agencies quote monthly and salaries are quoted annually, which is why nobody compares them properly. So annualise ours. A brand with around 30 SKUs on one marketplace doing £50,000 a month pays a £2,500 retainer plus £1,750 commission, which is £4,250 a month, or £51,000 a year. That sits below the fully loaded cost of one London hybrid hire, and it buys five disciplines rather than one person's calendar. Every number in that sentence is published, which is rare enough in this market to be worth holding up against whoever else you are talking to.
The honest objection to agencies is not price. It is that you meet senior people in the pitch and get a junior on the account afterwards. That is a fair thing to be suspicious of, and you should ask about it directly rather than politely. Here the work is founder-led, so the person on the first call is the person who runs the channel. Ask any agency who does the daily work and how many other accounts that person is carrying.
None of which makes in-house wrong. Above Build Grow Scale's threshold, or where Amazon has become the business rather than a channel inside it, an internal team accumulates institutional knowledge that no external party can hold in the same way, and plenty of brands end up running both. Below it, the arithmetic is doing the arguing. Fee ranges across the three charging models are set out in a separate post, and every engagement here opens with a free account audit, so you can judge the standard of the thinking before you price it against a salary.