An advertising agency plans, creates, buys and manages paid ads for a business. That covers strategy and media planning, the ads and landing pages, running spend on Google, Meta, LinkedIn and connected TV, tracking which dollars turn into booked jobs, and weekly testing. For a local business, it works like an outside ad department.
Most owners who hire an agency never see most of that work. They get a monthly report full of impressions and clicks, no login to their own ad accounts and no clear answer on which ads brought in paying customers. This is the exact gap we close through our advertising services in NJ.
What Does an Advertising Agency Do Day to Day?
If you have never hired one, the monthly fee can feel like a black box. Here is the work, in order.
It starts with strategy and media planning. Before a dollar goes out, the agency decides 3 things: which channels to use, how much to spend on each and what offer to lead with. A roofer after a storm might put most of the budget on Google search. A new product might lean on Meta and video, because nobody is searching for it yet. The offer matters as much as the channel. In our experience, "Free inspection this week" beats "Family owned since 1998" almost every time.
Next comes creative. The agency writes and designs the ads, shoots or edits the video and builds the landing pages the ads point to. Sending a strong ad to your homepage wastes money, because the homepage explains the company instead of asking for one action.
The spending plan should follow the math, not a round number. In our experience, most service businesses spend 5 to 10 percent of revenue on marketing, and agencies typically charge $1,500 to $10,000 a month to manage it, on top of what you pay Google or Meta. For the next step, read our post on how much advertising costs.
How an Advertising Agency Buys and Manages Media
Buying media is the part most people picture. Each platform does a different job:
- Google search ads catch people already looking for your service, so they usually carry the most buying intent.
- Meta ads on Facebook and Instagram create demand by putting an offer in front of people who fit your customer profile.
- LinkedIn ads reach business buyers by job title and company size, which matters for B2B services with bigger tickets.
- Connected TV runs video ads on streaming apps in the zip codes you serve, which builds the name recognition that shows up later as searches.
Managing that spend is weekly work. Someone sets bids and budgets, adds negative keywords so you stop paying for the wrong searches, moves money toward the ads that produce leads and pauses the ones that do not. Local service clicks on Google commonly run $5 to $50, so a few weeks of neglect can cost real money.
Some plans also include offline media such as billboards, radio or direct mail. Those work best when they point people to the same offer and landing pages the digital ads use, so you can see the lift. We go deeper on this in our post on billboard advertising costs in New Jersey.
How an Advertising Agency Tracks, Tests and Reports
Clicks and impressions are easy to report and easy to make look good. The number that matters is cost per booked job: what you paid in ads and fees for each customer who actually scheduled work.
What counts as a booked job depends on the business. For a roofer it is a scheduled inspection. For a car dealership it might be a test drive or a service appointment. At BMW of Sterling, one LinkedIn video produced a $60,000 service ticket. The same problem looks different by vertical, as our page on marketing for automotive dealerships shows.
Getting to that number takes setup: conversion tracking on every form, a link between the ad platforms and your CRM or sales sheet, and someone who checks that the leads are real. Without it, the platforms will count spam form fills and duplicate leads as wins.
Then comes testing, week to week. One headline against another, one offer against another. Each test answers one question, and the winner becomes the new baseline.
Account management keeps it honest. A named person should explain what changed this week, why, and what it did to your cost per booked job. If nobody can answer that in plain English, the account is on autopilot.
If you are not sure your ads are tracked to booked jobs, the free Growth Score shows where the gaps are. Take the free Growth Score →
Advertising Agency vs Marketing Agency: What Is the Difference?
Here is the plain version. An advertising agency buys and manages paid media and makes the ads that run on it. A marketing agency covers that plus the rest: SEO, content, social media, websites, CRM and overall strategy.
The difference matters because ads do not work alone. Paid clicks land on your website. Leads go into your CRM. Buyers check your reviews and social pages before they reach out. If a different vendor owns each piece, nobody owns the result, and each one can point at the others when leads slow down.
At ABMG, we sit on the marketing agency side. One team runs paid ads on Google, Meta and LinkedIn alongside SEO, content and video, social media, web design and CRM, so the ad, the landing page and the system that catches the lead are built by the same people. You own every account, file and asset.
What to Expect From an Advertising Agency
A good agency asks for things before it promises anything.
What a good agency asks for
- Admin access to your ad accounts, analytics and website, in your name so the history stays with you.
- Your sales data, even a simple spreadsheet of leads and closed jobs, so the ads are judged by revenue and not clicks.
- One decision-maker who can approve offers, budgets and creative within a few days.
What you should get back every month
A monthly report should fit on one page and answer 4 questions: what you spent, how many leads and booked jobs it produced, what each one cost, and what the agency tested and plans to change next. Screenshots of dashboards do not count as answers.
Red flags to watch for
- The agency owns your ad accounts, or will not give you access to them.
- Reports lead with impressions, reach and clicks, with no line for leads or booked jobs.
- A long contract that locks you in before results show up.
- Nobody can tell you what was tested last month or why the budget moved.
How to Judge an Advertising Agency's Results in 90 Days
A 90-day window is fair. The first month goes to tracking, setup and the first round of creative. The second month gives the platforms enough data to learn. By the third month, you should see cost per lead falling and more booked jobs, or a clear explanation of what is being fixed.
Here is what that looks like in our own work. A New Jersey roofer came to us paying $912 per lead on Google Ads. After a rebuild, cost per lead dropped to $197 and conversions went from 21 to 196 in 90 days, at a 15.62% click-through rate. CapYear Academy, on Meta instead of Google, earned a 1,774% return on ad spend: $66,176 in enrollment revenue on $3,729 of spend.
Events work the same way, with a harder deadline. In one recent engagement, we grew Flag Cities 2026 from 200 tickets to more than 47,000 fans.
Flag Cities is a soccer fan festival with 7 events, so every date was its own deadline, with no next month to fix a slow week.
Whatever you hire, judge it by cost per booked job and keep every account in your name. And do not let one channel carry the whole business, because the one that works today can get expensive fast. For a real-world take, read our post on why the channel that built your business will betray it.
Need a campaign that reaches the right buyers across channels? Plan your next campaign with our NJ advertising team.
Frequently Asked Questions
Is an advertising agency the same as a marketing agency?
Not quite. An advertising agency buys and manages paid media and makes the ads that run on it. A marketing agency covers that plus SEO, content, social media, websites, CRM and strategy. If your website and tracking are already solid, an ad agency may be enough. If they are not, one team across all of it usually gets further, because ads depend on every piece around them.
How much does an advertising agency charge?
In our experience, agencies typically charge $1,500 to $10,000 a month for management, plus the ad spend you pay the platforms directly. The range depends on how many channels are involved and whether creative, video and landing pages are included. At ABMG, published engagement tiers run $3,500 to $6,500 per month plus ad spend, and every account stays in your name.
How long does it take to see results from an advertising agency?
Expect the first 30 days to go to tracking, setup and the first creative. By 60 days the platforms have enough data to learn, and by 90 days you should see a clear trend in cost per lead and booked jobs. Search ads often produce leads in the first few weeks, while awareness channels like connected TV take longer to show up in the numbers.
