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ROI comparison custom online shop and marketplace

ROI Calculator: Custom Online Shop vs. Marketplace

Marketplace commissions eating your margins? Calculate when your own online shop pays off.

In brief

Break-even by annual revenue

At high annual revenue, from €70,000, break-even for an owned shop typically sits at 12 to 18 months. €21,000 a month at 15 percent commission falls in that band.

Compare commission with an owned shop

ROI calculator

Own online shop vs. marketplace sales

Does an own shop pay off compared to marketplace fees? Compare commissions with investment and operating costs.

Step 1 of 813%
30,000 €
5,000 €500,000 €

How the owned-shop break-even is built

The calculation follows six visible stages. All figures remain planning values until scope and assumptions have been reviewed.

  1. 1. Capture inputs

    The calculator records the visible project, volume, complexity and operating parameters selected on this page.

  2. 2. Add fixed components

    One-off investment and recurring operating components are added separately.

  3. 3. Apply multipliers

    Volumes, time values and rates are multiplied where the model converts effort or incidents into monetary effects.

  4. 4. Create the range

    The calculator applies its documented lower and upper uncertainty factors to the base result; ROI views keep investment and savings visible separately.

  5. 5. Round and calibrate

    Monetary result fields are rounded to the nearest whole euro. Public project-cost components are calibrated with the centrally maintained display factor.

  6. 6. Classify the result

    The result is shown as non-binding guidance. A binding quote requires scope, data, integrations, risks and acceptance criteria to be reviewed.

Included

  • Inputs shown in the calculator
  • Calculator-specific base values and factors
  • Displayed one-off and recurring result components

Not included

  • Requirements not selected in the calculator
  • Unknown data migration and third-party licence costs
  • Taxes, legal advice and a binding delivery commitment

Efficiency or discount factor: A central display factor of 0.7 is applied to public project-cost components to keep all calculators aligned with the currently reviewed pricing basis. It is not a customer-specific discount; customer-entered wages, revenues and existing operating costs are not reduced.

Why this is not a binding quote: The calculator cannot verify complete requirements, third-party dependencies, data quality, legal constraints or acceptance criteria.

Technical responsibility and review

Technical owner
Björn Groenewold
Role
Managing Director and software engineer
Expertise
Software development and software estimation
First published
Last technical review
Price basis
September 2026

Sample calculations & scenarios

Concrete project profiles with assumptions and indicative budgets—useful for internal alignment alongside the calculator.

Cost examples

All cost examples for this calculator

Marketplace commissions grow with your revenue, while the costs for your own shop remain relatively constant. Our ROI calculator shows when the investment in your own online shop pays off and how much you save over 5 years through saved commissions.

Marketplace commissions scale linearly with your revenue – at 15% commission and €140,000annual revenue, you're already paying €21,000 in fees alone. The costs for your own shop, on the other hand, remain largely fixed. There's also an often underestimated factor: on marketplaces, customer data doesn't belong to you. Your own shop gives you full control over customer relationships, email marketing, and repeat purchases – creating long-term business value that far exceeds the pure commission savings.

Why Marketplace Commissions Eat Your Margins

Growing Fees

At €70,000 annual revenue, 12% commission already costs €8,400 per year – and increases with every additional euro of revenue. With your own shop, costs remain constant at approx. €2,100 – 4,200/year.

No Customer Data

Marketplaces don't give you email addresses or contact details of your customers. Direct marketing, repeat purchases, and customer retention are difficult. Your own shop gives you full control.

Dependency

Marketplace rules can change at any time, accounts can be suspended, and algorithms determine your visibility. Your own shop gives you independence and control over your business strategy.

Typical Break-Even Timeframes

12–18 Months
High Revenue
  • €70,000+ annual revenue
  • High marketplace commission (12–15%)
  • Standard shop sufficient
18–30 Months
Medium Revenue
  • €35,000 – 70,000 annual revenue
  • Custom features desired
  • Long-term brand building
30+ Months
Low Revenue / Strategic
  • Under €35,000 annual revenue
  • Focus on brand building
  • Long-term investment

Finance Your Investment: Leasing & Subsidies

The investment in an owned shop sits in the range EUR 5,950 – 99,645 excl. VAT. The upfront spend can be spread over 72 months. Terms are on the software financing page. Whether the rate sits below the commission you stop paying is what the calculator shows with your revenue.

E-commerce projects can qualify for grants when they open online sales or extend a store. Which rule applies is what the funding calculator shows.

FAQ

Custom Online Shop vs. Marketplace

Costs & Benefits

When is a custom online shop worth it?

An owned shop pays off when commission grows with revenue.

From €70,000 a year, break-even sits at 12 to 18 months. Between €35,000 and €70,000 it sits at 18 to 30 months. Below that, often more than 30 months.

What does a custom online shop cost?

The investment varies depending on requirements: Standard shop (e.g., Shopware, WooCommerce) from EUR 5,950 – 99,645 excl.

VAT plus VAT. Custom shop with special features this calculator-derived range plus VAT. Enterprise shop with complex integrations this calculator-derived range plus VAT. Ongoing costs are this calculator-derived range/month for hosting, maintenance, and updates.

What ongoing costs does a custom shop incur?

Ongoing costs include: hosting and SSL certificate €35 – 140/month, maintenance and updates €70 – 350/month, payment provider fees (approx.

1–2% of revenue), shipping provider integration, and marketing tools (optional). Typically €140 – 700/month total plus transaction fees – significantly less than marketplace commissions at higher revenue.

What advantages does a custom shop have over marketplaces?

Advantages: No commissions (saves 5–15% of revenue), full control over customer data and marketing, better SEO opportunities, custom features and design, no dependency on marketplace rules, and long-term brand building.

Disadvantages: Higher initial investment, own marketing required, and technical responsibility.

Björn Groenewold – Geschäftsführer Groenewold IT Solutions

Discuss online shop ROI

We advise on break-even, revenue and next steps.

Book a call

Implementation & Operation

How quickly can I launch a custom shop?

A standard shop can go live in 4–8 weeks: 1–2 weeks planning and design, 2–4 weeks development, 1–2 weeks testing and go-live.

For custom requirements, it takes 2–4 months. You can already prepare marketing in parallel. ROI begins from the first sale – without marketplace commissions.

Can I run a marketplace and my own shop in parallel?

Yes, many merchants start with marketplaces and build their own shop in parallel.

This way, you leverage marketplace reach for your entry while simultaneously developing your own brand. Your own shop can later become the main sales platform, while marketplaces serve as an additional sales channel.

Will I lose reach if I leave the marketplace?

No, because we recommend a multi-channel strategy: your own shop becomes the main platform, while marketplaces can remain as supplementary sales channels.

Through SEO, email marketing, and social media integration, you build your own reach that belongs to you long-term – independent of marketplace algorithms.

Which payment providers can be integrated?

All common payment providers: Stripe, PayPal, Klarna, Mollie, Apple Pay, Google Pay, as well as classic payment methods like credit card, direct debit, and invoice.

Integration is seamless so your customers can use their preferred payment method. Transaction fees are 1–2%, significantly lower than marketplace commissions.

How much effort is involved in running your own shop?

With professional hosting and a maintenance contract, operational effort is minimal.

We handle updates, security patches, and performance optimization. You focus on your core business – products, marketing, and customer service. Technical operations typically cost €140 – 350/month, making it predictable and manageable.

ROI calculators

Inputs in the commission comparison

Which inputs move the commission comparison

Four checks: annual revenue, commission rate, fixed shop costs, and whether customer data stays with the marketplace.

  1. 1. Pick the revenue band

    From EUR 100,000 a year the range is 12 to 18 months. Between EUR 50,000 and 100,000 it is 18 to 30 months. Below that, often more than 30 months.

  2. 2. Keep commission on the marketplace

    15 percent on EUR 30,000 a month is EUR 360,000 a year and falls in the short band, not in a single month.

  3. 3. Keep shop costs fixed

    Hosting, maintenance, and payment fees do not grow with every euro of revenue the way commission does.

  4. 4. Value customer data separately

    Email and repeat purchase are not on the commission curve. They belong in the business case.

Typical pricing models (overview)

Comparison: typical pricing models for software and IT projects
ModelWhen it fitsBudget & flexibilityTypical risks
Fixed price (fixed scope)Clearly defined scope, stable requirements, repeatable delivery.Predictable total cost; little room for change without a change order.Scope creep leads to change orders or quality trade-offs.
Time & MaterialDiscovery, legacy, evolving requirements, or close collaboration.Maximum flexibility; budget transparent via hourly or daily rates.Without prioritisation, effort can grow—backlog and reviews matter.
Retainer / maintenance packageOngoing operations, updates, small features, and support.Agreed capacity per month; predictable follow-on cost.Large changes may still need a separate estimate.
Hybrid (milestone + T&M)MVP or phased releases with clear go-lives, then iterate.Core delivery fixed price; extensions on a time-and-materials basis.Define contractually what is in scope vs. extra work.

Calculators on this page provide indicative ranges; we choose the right model with you based on risk, scope, and planning horizon.

What determines the costs, and what comes next?

The ranges shown are indicative. For a binding quote we discuss scope, priorities and funding options in a free intro call. Many digitalization projects qualify for grants – try our funding calculator.

Browse all cost calculators, explore services and typical solutions. Questions about online shop ROI? Contact us.

After using the online shop ROI calculator, validate assumptions in a short intro call.

What we align in the call

  • Scope, risks, and funding options
  • Milestones and documented exclusions
  • Transparent quote without hidden line items

Costs for online shop ROI in context

  • Scope, risk, and quality expectations drive the range
  • Include operations, maintenance, and grants
  • Dedicated contacts and short paths from East Frisia

Browse all cost calculators in the costs overview.