Yes, both Campaign Monitor and Slemma offer a Free Trial.
Campaign Monitor is designed for Freelancers, Large Enterprises, Medium Business and Small Business.
Slemma is designed for Medium Business and Small Business.
The starting price of Slemma begins at $89/Month when Billed Yearly, while pricing details for Campaign Monitor are unavailable.
Some top alternatives to Campaign Monitor includes Pipedrive, Campaigner, Moosend and SMTP.
Some top alternatives to Slemma includes Alteryx, iDashboards, DataHero, Databox, DashThis, Klipfolio Dashboard, myDATA3, Easy Insight, AppInsights and Analytics Canvas.