Yes, both Help Sumo and Zendesk Support offer a Free Trial.
Help Sumo is designed for Large Enterprises, Medium Business and Small Business.
Zendesk Support is designed for Large Enterprises, Medium Business and Small Business.
Pricing for Help Sumo Starts at $19/User/Month whereas for Zendesk Support Starts at $19/user/month when yearly.
Some top alternatives to Help Sumo includes Zendesk Support, Zoho Desk, Tidio Helpdesk, Freshservice, Freshdesk, ProProfs Help Desk, Support Hub, HelpDesk, SysAid, Jitbit Helpdesk, Desky, ReadyDesk, HelpdeskEddy, LabiDesk, AzureDesk and Help Desk Premier.
Some top alternatives to Zendesk Support includes Zoho Desk, Tidio Helpdesk, Deskero, Support Hub, HelpDesk, Desky, Help Scout, Salesforce Service Cloud, ReadyDesk, Sitehelpdesk, HESK and BoldDesk.