CiviCRM - A Constituent relationship management for the Civic Sector
Cozy.co - Modern property management for landlords, property managers, and renters.
Odoo CRM - Open Source CRM
Anabode - Anabode is a smart property management platform for landlords & property managers of all sizes. Manage, Repair & Keep Track of your properties, anywhere in the world. Get started for free. No credit card required.
Salesforce - CRM software solutions and enterprise cloud computing from salesforce.com, the leader in CRM and platform as a service.
Rentec Direct - Online property management software for landlords and property managers.