If i am to buy a license for DayPilot Pro, i.e: 2500 for DayPilot Pro for ASP.NET WebForms (Web Office).
What is the cost of renewal? Or is it a one time only fee?
The initial purchase includes 12 months of maintenance (upgrades and support). The renewal is 20% of a new license price per year (i.e. $499 for the Web Office license).
The renewal is optional. If you decide not to renew the maintenance you can still use the older versions (that were released during the time your maintenance was active).