Yes, both HourStack and Sunsama offer a Free Trial.
HourStack is designed for Medium Business and Small Business.
Sunsama is designed for Large Enterprises, Medium Business and Small Business.
Pricing for HourStack Starts at $9/Month when Billed Yearly whereas for Sunsama Starts at $16/Month when Billed Yearly.
Some top alternatives to HourStack includes TimeCamp, TrackingTime, TimeTrack, Busy, Timebase, TeamTime, Sunsama, Tack, Timet and TimeTackle.
Some top alternatives to Sunsama includes Todoist, Wrike, Smartsheet, Asana, nTask, Microsoft To Do, TickTick, Today, Any.do, MeisterTask, ClickUp and TasksBoard.