Checkout vtiger CRM, its pretty much open source version of sugar CRM. Advantages: Complete CRM is opensource, no hidden paid features, there are wide list of

Checkout vtiger CRM, its pretty much open source version of sugar CRM. Advantages: Complete CRM is opensource, no hidden paid features, there are wide list of free extensions. Few are paid . community support is also good. Disadvantages: Not much of good UX. You might need to customize to get better user experience.