Generated +$50M for +73 E-com brands & Info Products in 12 countries

We scale E-commerce brands past $100k/month without damaging profitability.

Watch the video below to learn how it works.
Hands-on experience from
our own 2 E-commerce brands.
If we're not profitable, you don't pay for our service. Our success is tied directly to your success.
5.0/5.0 from
+30 E-commerce brands on Trustpilot

Our clients

80k

followers

Scandinavia's fastest growing boheme fashion brand.

314k

followers

#1 Worldwide brand for toe spacers & foot health education.

80k

followers

DogCoach is Europe's #1 Dog Owner Clothing Brand

2k

followers

Scandinavia's fastest growing soil & plant webshop.

4.9k

followers

#1 Online tech school with over 21.000 students worldwide, focusing on diversity.

43k

followers

The Beautiful Game is one of Netherlands' fastest growing football webshop & community.

Our results speak louder than our words

One-Product Store
£910k from just £164k ad spend in one month

Revenue driven primarily from Meta & YouTube ads while utilising listicle & advertorials.

  • 6.24x ROAS
  • 16% MER
  • 5.60x NC-ROAS
Fashion Brand
43% revenue growth in 8 months

Driving growth through Meta & Google focusing on new customers we increased revenue by 43% while keeping ROAS & CAC the same.

Supplement Brand
+107% revenue increase for a supplement brand

In less then 2 months of working with this supplement we achieved:

  • +20% increase in POAS (Profit on Ad Spend)
  • 160% increase in net profit
  • +82% increase in Ad Spend
Fashion Brand
51% revenue increase in 4 months

Despite a low conversion rate we increase new customer revenue drastically while keeping AOV at +€200.

Success cases

We don’t just drive short-term wins — and we're proud to say that our average retention is 19.7 months. (Updated April 2026)

Europe's #1 Glamping Booking Site
Owayy (now campanyon)
+437% Revenue Increase
Opened up +4 markets
+1.5 year retention
Europe’s #1 Dog Owner Apparel Brand
DogCoach
+120% revenue growth
Opened up +4 markets
+3 years retention
From Local Boutique to Scandinavian Icon
Åberg Copenhagen
+2.000% revenue growth in 3 years
From Local to Scandinavian Fashion Brand
+3 years retention
Sweden's Biggest Fitness Coach
Hampus Botvid
40% Cheaper Conversions
41% Cheaper Leads
Scandinavia’s #1 Soil Delivery Service
Svedberga
142% Revenue Growth in 2024
93% AOV Increase
+15 months retention
Denmark's #1 Plus Size Fashion Store
Curved
From $578K/year to $1.9M in 24 months
63% ROAS Increase
+4 year retention
#1 Health & Fitness Course in Denmark
Louise Bruun
Increased ROAS from 5.2x to 6.1x
22% Revenue Growth YoY
+3 year retention
Effortless Style, Remarkable Growth
The Shirt
From $15K/month to $81K in 16 months
275% ROAS Increase
+4.2 year retention
Europe's #1 Glamping Booking Site
Owayy (now campanyon)
+437% Revenue Increase
Opened up +4 markets
+1.5 year retention
Europe’s #1 Dog Owner Apparel Brand
DogCoach
+120% revenue growth
Opened up +4 markets
+3 years retention
From Local Boutique to Scandinavian Icon
Åberg Copenhagen
+2.000% revenue growth in 3 years
From Local to Scandinavian Fashion Brand
+3 years retention
Sweden's Biggest Fitness Coach
Hampus Botvid
40% Cheaper Conversions
41% Cheaper Leads
Scandinavia’s #1 Soil Delivery Service
Svedberga
142% Revenue Growth in 2024
93% AOV Increase
+15 months retention
Denmark's #1 Plus Size Fashion Store
Curved
From $578K/year to $1.9M in 24 months
63% ROAS Increase
+4 year retention
#1 Health & Fitness Course in Denmark
Louise Bruun
Increased ROAS from 5.2x to 6.1x
22% Revenue Growth YoY
+3 year retention
Effortless Style, Remarkable Growth
The Shirt
From $15K/month to $81K in 16 months
275% ROAS Increase
+4.2 year retention
Europe's #1 Glamping Booking Site
Owayy (now campanyon)
+437% Revenue Increase
Opened up +4 markets
+1.5 year retention
Europe’s #1 Dog Owner Apparel Brand
DogCoach
+120% revenue growth
Opened up +4 markets
+3 years retention
From Local Boutique to Scandinavian Icon
Åberg Copenhagen
+2.000% revenue growth in 3 years
From Local to Scandinavian Fashion Brand
+3 years retention
Sweden's Biggest Fitness Coach
Hampus Botvid
40% Cheaper Conversions
41% Cheaper Leads
Scandinavia’s #1 Soil Delivery Service
Svedberga
142% Revenue Growth in 2024
93% AOV Increase
+15 months retention
Denmark's #1 Plus Size Fashion Store
Curved
From $578K/year to $1.9M in 24 months
63% ROAS Increase
+4 year retention
#1 Health & Fitness Course in Denmark
Louise Bruun
Increased ROAS from 5.2x to 6.1x
22% Revenue Growth YoY
+3 year retention
Effortless Style, Remarkable Growth
The Shirt
From $15K/month to $81K in 16 months
275% ROAS Increase
+4.2 year retention

Our services

+5 years of experience and one E-com brand exit.

Paid advertising

We're a lean team of 3 full-time paid advertising specialists with experience of handling accounts spending +$1M/month.

Creative execution

We take care of your content management from A-Z. We craft the perfect content mix consisting of static ads, GIF ads, UGC & Professional video ads.

Funnel & strategy

We craft strategies and funnels designed to take potential customers from a complete unaware stage to being an educated buyer.

Retention marketing

We make sure your customers buy again & again through Email & SMS marketing increasing your profit margins and allowing you to run with a higher CAC.

Why do E-com brands  
choose us?

In-house growth partner for established E-commerce businesses

Scaled 2 of our own brands + 1 exit
Generated +€100M in revenue through Meta Ads
Here's proof

Description of our approach

Most brands we work with have tried other agencies first. The difference is we don’t start by tweaking bids or buttons. We start by fixing the gaps in your funnel and the messaging. Our system is built on consumer psychology, not guesswork.

We partner with our clients for years

We're proud to have an average retention of 19.7 months which also means that some of our clients have been with us for over 4 years at this point. There's a reason for this. We've been on the other site of the table, built, owned and sold an E-commerce business. This gives us the ability to act as a growth partner that truly understands the business you are running, and can support or give advice on areas that isn't directly correlated with advertising.

Free Performance Analysis
Apply for a free
performance review by Lucas Lucas

Sign up today to get a taste of how we operate and how we can help you scale. We will analyze your entire marketing setup and show you exactly where you need to optimize to increase your revenue and profit. This includes a review of your ad accounts, website/webshop, content, and ad copies.

Analysis of your digital presence & growth potential.
A complete growth strategy to take your advertising to the next level.
We will analyse your ad accounts, copywriting, ad creatives, website / landing pages and email marketing automation.
Analysis of your best performing markets & how to expand into new markets.
30-minute live walkthrough of all our findings with our CMO.
BONUS: Customer journey analysis to show you how to increase profit by up to 80%. (9/10 businesses are missing out on this)
We require you to be able to spend $3.000 or above on your monthly advertising to qualify for our performance review.

Start the conversation with us today, by applying for a free review of your digital presence and growth potential.

Can't find a suitable time?
Can't find a suitable time?

Schedule your free Performance Review call.

Thanks for applying! For us to give you a comprehensive Performance Review, please schedule your 15-30 minute call by clicking the call below. This is required for us to continue with your application.

We will analyze your entire marketing setup and show you exactly where you need to optimize to increase your revenue and profit. This includes a review of your ad accounts, website/webshop, content, and ad copies.

The call is perfect for:

Businesses who seek to understand which improvements can be made to their current marketing strategy.
Businesses that are ready for massive growth.
Businesses looking for a proactive partner with 5+ years of E-commerce experience to make their business a priority.
Official partners of leading platforms:
Oops! Something went wrong while submitting the form.
Apply for a free
performance review by Lucas Marcus

Sign up today to get a taste of how we operate and how we can help you scale. We will analyze your entire marketing setup and show you exactly where you need to optimize to increase your revenue and profit. This includes a review of your ad accounts, website/webshop, content, and ad copies.

Analysis of your digital presence & growth potential.
A complete growth strategy to take your advertising to the next level.
We will analyse your ad accounts, copywriting, ad creatives, website / landing pages and email marketing automation.
Analysis of your best performing markets & how to expand into new markets.
30-minute live walkthrough of all our findings with our CMO.
BONUS: Customer journey analysis to show you how to increase profit by up to 80%. (9/10 businesses are missing out on this)
We require you to be able to spend $3.000 or above on your monthly advertising to qualify for our performance review.

Start the conversation with us today, by applying for a free review of your digital presence and growth potential.

Can't find a suitable time?
Can't find a suitable time?

Schedule your free Performance Review call.

Thanks for applying! For us to give you a comprehensive Performance Review, please schedule your 15-30 minute call by clicking the call below. This is required for us to continue with your application.

We will analyze your entire marketing setup and show you exactly where you need to optimize to increase your revenue and profit. This includes a review of your ad accounts, website/webshop, content, and ad copies.

The call is perfect for:

Businesses who seek to understand which improvements can be made to their current marketing strategy.
Businesses that are ready for massive growth.
Businesses looking for a proactive partner with 5+ years of E-commerce experience to make their business a priority.
Official partners of leading platforms:
Oops! Something went wrong while submitting the form.

Learn from Marcus on YouTube

Raw & straight-to-the-point YouTube videos about how to grow your E-commerce brand profitably.

Customer voices

Hear what our customers say about their experience with us. Genuine stories of satisfaction and success

I highly recommend Marcus from Complex Solution—he has a great service mindset, is a problem-solver, creative, and quick. Marcus is always available and always ready to try out new ideas. He provides weekly updates, constantly monitors conversions, ROAS, ad spend, etc. He also focuses on increasing revenue/conversions and providing guidance on problem-solving. We at Åberg Copenhagen look forward to a long and fruitful partnership, which we are very excited about so far. Best regards, Needa Violaaurora CEO & Founder Åberg Copenhagen
Pia åberg
We at DogCoach have had the pleasure of collaborating with Marcus & Complex Solution since 2022. During this period, DogCoach has both expanded into new markets and significantly grown the company in B2C sales. Unlike larger agencies, we experience a tremendous effort put into both understanding the brand and the company, as well as working proactively and committedly. Furthermore, Marcus always participates actively and is adept at considering the company as a whole.
Here you get a comitted wingman who thinks independently and where reporting and data are done on a high level. Marcus & Team get my absolute highest recommendations.
LR
Linn Radsted
Highly recommended! Marcus has been managing our Facebook Ads for about three months now and has delivered impressive results throughout. We’re averaging an ROAS of 13 and have generated an additional revenue of 500,000 DKK in the short time we’ve been working with him.
Marcus is independent-minded and proactive, and works incredibly hard to deliver the best possible results for his clients!
AF
Anton Frederik
I highly recommend both Marcus and Mads. We at Curved.dk have been working with them for over a year now. We’re growing every single month, and they’re always ready to help and do a fantastic job.
They are 100% honest and easy to talk to, so I can vouch for them anytime.

Thank you, Marcus and Mads, for everything so far; I look forward to many more months working with you.
LF
Lone Frandsen
Have worked with Marcus for about a year, and it has been a very pleasant experience. Marcus always delivers on time and replies immediately. I have worked with different larger teams before, where I got a new account manager constantly, and with that, had to spend a lot of time troubleshooting. With Marcus it's nice to know that won't happen, and it saves me a lot of time.
My best recommendations ⭐️⭐️⭐️⭐️⭐️
D
Ditte
I am extremely impressed with the results. The company's communication and dedication to our campaign has been top-notch. Every week, they provide us with a video update explaining the progress and strategies being implemented to improve our results.

One of the things that I appreciate the most about Complex Solutions is their dedication to constantly improving our website to get better results with our Facebook-Ads. They have provided us with valuable feedback and suggestions on how to optimize our website for conversions, which has significantly increased our click-through rates.

Moreover, the team has been very receptive to our suggestions and ideas, and they have always been quick to implement any changes or adjustments that we have requested. This level of flexibility and willingness to listen to their clients' needs is what sets this Complex Solutions apart from others in the industry.

I highly recommend Complex Solutions for anyone looking to set up and manage their Facebook-Ads.
HF
Hello Floor

Frequently Asked Questions

Here's some of the most frequently asked questions we get.

How do you work with clients, is it performance-based or retainer?

If you’re scared of retainers or performance fees we’re not the right fit. We mostly work on a mix between the two with a lower retainer and a performance fee to make sure both your company and ours are compensated when you grow.
No free-trials or test period.
We’re not here to fix your business, we’re here to create leading E-commerce brands.

What’s the difference between your approach and what my current agency is doing?

We don’t know what your agency is doing or what their thought is, and it might also be that they are doing incredibly well. With that said we can say that the team we've built, knows what it actually takes to profitably spend more than $20k/month on ads which is where most people hit a ceiling. We’ve run our own E-commerce businesses with revenue in the millions, and have managed to scale multiple clients to 7 and even 8 figures in yearly revenue.

What’s expected from us on a weekly basis?

We’ve experienced a lot of times that E-com brand owners think an agency can run the entire business or save it from failing, and the truth is.. we can’t. You have to continue innovating on your product, improve customer service, find better suppliers, cut your costs to improve profitability and everything in between. We will then take all of your hard work and multiply it through ads generating exponential growth.

How quickly should I expect new ads to be launched?

Our onboarding process typically takes 7 days from our onboarding call to having done all of our research and then we start on the first creative batch which is typically launched within 5-7 days. In 9 out 10 cases we launch new ads within 14 days of starting our collaboration.

What platforms do you handle?

For 90% of our clients we handle Meta & Google Ads alongside Email & SMS marketing. These are typically the most important channels.

We do also handle Snapchat, Pinterest & TikTok ads for our clients if we believe it can add incremental revenue to your business.

Who will I be communicating with?

We have no account managers or customer success representatives. You will be in direct contact with our founders and the people actually running your ads.

Do you work with long binding contracts?

We believe that our work and communication is enough for you to stay, if not, you're free to leave on a month by month basis. We do expect you to commit at least 3 months, since we're not a quick fix and do not work with quick tactics or hacks to grow your business.

Do you work with Email & SMS marketing?

Absolutely. We know that paid ads continues to get more and more expensive every year, and the best way to combat that and protect your margins, is to ensure your customers comes back again & again. That is why Retention Marketing is an essential part of our marketing strategies.