How much is the price for the yearly maintenance contract on a 20 user package of Zulu and how much e.g. on a 25 year 1000 user package?
1 Year license on zulu are yearly renewals to continue using the product so they have no maintanace cost since its a yearly service.
If you buy the 25 year license then maint renewal for upgrades are just like all other commercial modules at 18% a year if the module is over 100.00 cost and 33% if the module is under 100.00 so in Zulu case it would be 18% a year for upgrades.
This is all outlined here and reference in our store and on the invoices durning checkout. http://literature.sangoma.net/EUA/FreePBXCommercialModule-EndUserAgreement.pdf