Yes, both Zendesk Support and RingCentral Office offer a Free Trial.
Zendesk Support is designed for Large Enterprises, Medium Business and Small Business.
RingCentral Office is designed for Large Enterprises, Medium Business and Small Business.
Pricing for Zendesk Support Starts at $19/user/month when yearly whereas for RingCentral Office Starts at $19.99/User/Month when Billed Yearly.
Some top alternatives to Zendesk Support includes Zoho Desk, ManageEngine ServiceDesk Plus, Deskero, Support Hub, HelpDesk, Desky, Help Scout, Salesforce Service Cloud, ReadyDesk, Sitehelpdesk, HESK and BoldDesk.
Some top alternatives to RingCentral Office includes RingByName, VoIPstudio, Vonage Business, 3CX, 4PSA VoipNow, Infobip, Voxloud, MightyCall, Ringover, Voxbi and AT&T Office@Hand.