Yes, both Constructor and Assembla offer a Free Trial.
Constructor is designed for Freelancers, Large Enterprises, Medium Business and Small Business.
Assembla is designed for Large Enterprises, Medium Business and Small Business.
Pricing for Constructor Starts at $5/User/Month whereas for Assembla Starts at $9.16/User/Month.
Some top alternatives to Constructor includes Jira, Assembla, Sprintly, Blossom, ClickUp, Swit, Webbing Labs, CoLab, Height, Collab Spot and Worktez.
Some top alternatives to Assembla includes Quickbase , Smartsheet, ClickUp, Zoho Projects, Jira, Wrike, TeamGantt, GitScrum, Teamwork, ProjectManager.com, Backlog, Axosoft, TaskBranch, Quick Base, Project.co and Height.