Yes, both Microsoft OneDrive for Business and Flow offer a Free Trial.
Microsoft OneDrive for Business is designed for Freelancers, Large Enterprises, Medium Business and Small Business.
Flow is designed for Large Enterprises, Medium Business and Small Business.
Pricing for Microsoft OneDrive for Business Starts at $1.99 whereas for Flow Starts at $6/User/Month when Billed Yearly.
Some top alternatives to Microsoft OneDrive for Business includes CollaborateCloud, Microsoft SharePoint, Onehub, ShareFile, Dropbox Business, FileCloud, Box, Citrix Content Collaboration, imDocShare and Microsoft 365.
Some top alternatives to Flow includes Quickbase , Smartsheet, ClickUp, Zoho Projects, Wrike, TeamGantt, Teamwork, ProjectManager.com, Microsoft Project, ProWorkflow, Trackboard, TaskBranch, Quick Base, Height, Task Flow and Project Insight.