Describe catalog requirements
Create examples of products, options, price groups, filters and delivery methods. Test these scenarios in each platform's demo build. A large number of products alone does not determine the winner: data structure, search, import, integration and quality of implementation are important.
Continue with: OpenCart launch: test the store before advertising.
Consider the editorial work
WooCommerce is appropriate to consider when the store is closely related to a WordPress site and active content work. OpenCart is worth evaluating for a catalog and commerce focused project. In both cases, check the convenience of a particular manager's day-to-day work: product editing, order processing and returns.
Continue with: Hourly development: estimates, rates and acceptance.
Count the dependencies
Budget for required extensions, license renewals, theme customization, CRM integration, and regular updates. For critical connectors, check the support for the required version. Complete the comparison with a "scenario - implementation - limitations - cost" table, not an overall ranking of the platforms.
Do you need to move your current store to another CMS?
Only when specific constraints justify migration. First, compare the cost of refining, migrating data, and saving search URLs.