Planning a e-commerce web app starts with the workflow, integrations, and release requirements. This guide uses an illustrative budget for the base scope below, with the decisions that can change the estimate. A project-specific quote follows a scope review.
Last updated: October 2026
€5,500–€20,000
Planning estimate in EUR for the base scope below. A written quote confirms the price, tax treatment, and payment terms.
6–14 weeks
Depends on agreed scope, access to services, feedback, and release requirements. Confirm availability and milestones before scheduling.
Share the main user workflow, required integrations, existing assets, and target platforms. We can then separate the first release from later features.
These figures are planning assumptions, not market averages, a fixed offer, or a guaranteed delivery date. Ongoing services and maintenance need a separate budget unless included in the proposal.
List the purchasing rules that an existing commerce platform cannot support through configuration. A standard catalog and checkout may not justify a custom build. Compare ongoing administration, integrations, and maintenance as well as the initial build.
Document stock changes, order edits, cancellations, partial refunds, and fulfillment updates. Decide which actions staff can perform themselves. Warehouses, tax rules, shipping providers, and accounting integrations should be named in the estimate.
Give each developer or team the same workflows, integrations, acceptance criteria, and release responsibilities. Ask what is excluded and how changes are priced. Compare handover documentation, testing, support, and recurring service costs alongside the build price.
Hosting, payment processing, email or SMS, third-party subscriptions, and ongoing maintenance should be budgeted separately unless explicitly included in the written proposal. Confirm current provider pricing for your expected usage and region. The planning range on this page is not a market survey or a fixed offer.
This guide uses an illustrative €5,500–€20,000 build budget for the listed base scope. The final quote depends on requirements, integrations, and acceptance criteria; it may fall outside this range.
The planning window is 6–14 weeks for the listed scope. Availability, feedback, dependencies, and release approvals affect the schedule. Milestones are agreed after the scope review.
I start by checking whether an existing commerce platform fits your purchasing and operations workflow. A custom build becomes worth discussing when a clear requirement cannot be met through configuration or a supported integration.