There is a popularly cited quote from GNU.org, that identifies the nuance:

"Free Software" is a matter of liberty, not price. To understand the concept, you should think of
"free" as in "free speech" not as in "free beer".

The code base of open source software is available to everyone and can be changed and reused as desired. But the intellectual property owner retains authorship of the code and can consequently reserve rights on its distribution as part of a commercial product. Consequently, open source software is not necessarily free of charge. CRM products in particular often come in at least two versions, a community version and a commercial version:

• the community version is provided at no charge and can be downloaded and installed without license fees
• the commercial version of the same software may add functional extensions and/or vendor support on top of the product for a fee

However, the license fees for an open source product are often a fraction of the costs of a commercial product, thanks to the low overhead of the vendor organization for distribution, marketing and sales and above all product development.

When considering open source software, one must be aware of the different types of open source licenses. That is not the topic of this whitepaper. If you want to understand more about open source licenses and the differences between them, please turn to the Optaros whitepaper "Free and Open Source Licenses, Software Development, and Distribution"