What does a marketing agency actually do — and what you can run yourself

Every founder asks me the same question before signing a retainer: what does a marketing agency do for that monthly fee? The honest answer is eight jobs. Four are thinking work, four are grinding work, and that split explains why two agencies quote $1,500 and $12,000 for what sounds like the same service.

I have bought those hours for a product business and I now build tools that replace a slice of them. Here is the version I wish someone had handed me first, with the SBA marketing guide open next to it.

What does a marketing agency do? The eight jobs, in plain words

A full-service retainer sells you eight jobs, whether or not anyone names them on the contract:

1. Strategy — who you sell to, what you promise, which channel goes first.
2. Positioning and offer — the page and the price that make the promise believable.
3. Creative — graphics, video and copy that stop a scroll.
4. Media buying — spending budget across Google, Meta and the rest.
5. Email and lifecycle — the flows that turn a sign-up into a payment.
6. SEO and content — pages that bring visitors without paying per click.
7. Social — posting and replying often enough to stay visible.
8. Reporting and analysis — the numbers that tell you what to change.

Most retainers price all eight. Most founders need three urgently, two occasionally, and can run one or two themselves from the first week. The tier-by-tier prices sit in what a marketing agency actually costs.

Strategy: the one job you cannot skip

Strategy is the cheapest deliverable and the most expensive mistake. It answers three questions: which customer, which promise, which channel first. Get it wrong and every other job just spends money faster. A focused workshop and a two-page document usually settle it — call it 4 to 6 hours of senior time.

This is the job I would never fully outsource. The agency knows the market; you know why people actually hand over money. Two founders in the same category can give completely different answers, and exactly one of those answers lives in your customer's head.

Creative: what "3 posts a week" really costs

Creative is where retainers quietly stretch. One reasonably produced 30-second video can take a videographer, an editor and a copywriter most of a day — BLS puts market research specialists alone at a median near $37 an hour, before anyone touches a camera. Three posts a week is 40-plus hours a month.

Ask for the source files at the end of every month: the project file, the raw footage, the layered design. If the answer is no, you are renting your own marketing. Switching agencies then costs you everything you already paid for, which is exactly why the files stay with them. Budget creative as its own line, separate from the fee, or it quietly becomes the reason the retainer grows.

Media buying and what the fee is for

Media buying looks like "put $3,000 into Meta Ads". The fee pays for the decisions: which audience to cut, which creative to kill, when to push budget. On a $3,000 monthly ad budget a 15% management fee is $450, which is small next to losing a week of testing on the wrong audience.

What you should demand is cost per acquisition, not impressions. If nobody can tell you what a customer costs you in each channel, you are buying activity. Two numbers fix that: CAC and LTV. And before another euro goes out, fix your tracking first — a broken conversion signal makes every decision after it a guess.

One more question worth asking: how much of the budget is testing new creative versus scaling what already works? A healthy answer keeps 10 to 20% in test at all times. An agency that only ever scales is running your account on last quarter's idea.

Email, search and social: the monthly grind

These three compound, and all three are grind work:

• Email: four flows carry most of the revenue before any newsletter goes out. Build them once, then maintain them.
• SEO: one solid article a week beats four thin ones a month. Results arrive in months, not days.
• Social: the replying matters more than the posting. Most accounts post daily and never answer anyone.

No agency can shortcut that. They can only take the hours off your desk. Count it honestly: two articles a week is about 8 hours of writing, editing and internal linking. A newsletter plus three automated flows is 15 to 20 hours once, then an hour a week. Social replies are 30 to 60 minutes a day if you answer people properly. That is most of a working week before anyone touches an ad account.

Reporting, or the slide you never read

Forty-page monthly reports exist to justify the retainer, not to help you decide. Ask for one page: spend, cost per acquisition, revenue, and the single change you should make next month. If a report cannot fit on one page, it is hiding something.

Pick four numbers and keep them for a year: new customers, cost per customer, average order value and repeat rate. Everything else is commentary.

Which jobs to keep and which to hand over

Two things I would keep permanently, whoever does the work: final approval on anything public, and the topic list that decides what you talk about. Everything else is production, and production gets cheaper every year.

What the same eight jobs look like with agents you approve

The reason this list matters is that the grinding half is now software. Agents can research the market, draft the creative, run the ad checks, set the email flows and write the article — the work a retainer actually bills hours for. You keep the decisions, and nothing goes live until you approve it. That is the marketing agency alternative most founders are looking for without knowing the name of it.

The difference is paying for hours versus paying for outcomes. Start for $1 and see what two weeks of that looks like on your own account.