In reply to Calum Allison (@calumallison).

Calum is absolutely right. The only sustainable model for long term plugin health are yearly (or perhaps bi-yearly) maintenance and support licensing. If you'd like the plugin you bought to wither on the vine, then pay only once.

I think yearly licensing fees shouldn't be more than 1/2 the price of a plugin though. A second year user is likely to need a lot less support.