CiviCRM is open-source. It's free to download and use.
The changes you make are all your own. It does not belong to a commercial company.
It has more features than many CRMs costing thousands.
You can develop and configure it yourself. Or if you use Xpdient, then you have an initial cost, but no on-going costs, no matter how many contacts.
There is a vibrant development and support community, helping people just like you.
It's built by and for organisations like yours.