Yes, both HESK and osTicket offer a Free Trial.
HESK is designed for Large Enterprises, Medium Business and Small Business.
osTicket is designed for Individuals, Large Enterprises, Medium Business and Small Business.
Pricing for HESK Starts at $24.91/Month when Billed Yearly whereas for osTicket Starts at $9/User/Month.
Some top alternatives to HESK includes Zoho Desk, Zendesk Support, ManageEngine ServiceDesk Plus, Freshservice, Freshdesk, Teamwork Desk, HelpDesk, SysAid, osTicket, Jitbit Helpdesk, CRMdesk, ReadyDesk, GetHelp, Sitehelpdesk, Trakdesk and Spiceworks Help Desk.
Some top alternatives to osTicket includes Zoho Desk, Zendesk Support, ManageEngine ServiceDesk Plus, Freshservice, Jira Service Desk, Freshdesk, HelpDesk, SysAid, UVdesk, Jitbit Helpdesk, eStreamDesk, ReadyDesk, Spiceworks Help Desk, HESK, BoldDesk and GLPI.