Yes, both Kayako and Trello offer a Free Trial.
Kayako is designed for Large Enterprises, Medium Business and Small Business.
Trello is designed for Individuals, Freelancers, Large Enterprises, Medium Business and Small Business.
The starting price of Trello begins at $5/User/Month when Billed Yearly, while pricing details for Kayako are unavailable.
Some top alternatives to Kayako includes Zendesk Support, Zoho Desk, Tidio Helpdesk, Freshservice, ManageEngine ServiceDesk Plus, Freshdesk, Deskero, Teamwork Desk, LiveAgent, HelpDesk, SysAid, Jitbit Helpdesk, CRMdesk, Sitehelpdesk, LabiDesk, HESK and BoldDesk.
Some top alternatives to Trello includes Quickbase , Smartsheet, ClickUp, Zoho Projects, Freshbooks, Jira, Basecamp, Wrike, monday.com, Asana, Teamwork, ProjectManager.com, Microsoft Project, Worksuite, Trackboard, Quick Base, Todoist, Resource Guru and Height.