The anonymous reader is looking for something free. SAP is short for "Send Another Payment"
SAP is decidedly not "free", BUT zero licensing cost is not free either.
Sometimes the most expensive option you can pick will be the free one!
The important thing to remember is software license cost is not your only cost.
Time and energy have to be invested in deploying whichever solution you pick and making it work;
in other words, shoehorning the software into the role, customizing as necessary, and forcing the employees to adapt to the requirements imposed by the software.
If you're not familiar with the software then probably you are not up to it yet.
Your company should probably be hiring other organizations to assist; Know your limits and seek outside help when appropriate.
Now there are plenty of commercial solutions; some of them may be a more appropriate fit for your organization than any one of the free ones.
They're worth investigation --- because whichever one you pick; your company will be investing and committing significant resources to the choice.
Being so enamored with a certain license cost, or distribution model is not appropriate for most businesses; these are "nice to haves" from a geeky point of view.
But the selection of which CRM application to use is a business decision that should not be constrained by trivialities like "free" --- whichever offering will benefit the company the most, seems the right choice. (It's probably not SAP)