Roel, the cost will definitely depend on your requirements and the number of software users in your company.
Here is an example of one of the most cost-effective CRM solutions – BPMonline CRM. The system is powerful, easy to use and customize and is delivered at an incredibly inexpensive price point – just $35 / month / seat.
What makes BPMonline stand out from the rest of CRM solutions is a professional business process management engine to design, automate, monitor, and supervise business processes.
Give it a try at http://www.bpmonline.com/autologin?locale=en
All the best!