Plugin upgrade routes and pricing. Your opinions sought.

What do you (the community) think is a reasonable cost of a version upgrade of a previously purchased plugin?

Personally I feel the upgrade cost should reflect the effort required for the plugin, so for examle, going from 1.x to 2.x is going to cost more but that asking for full price from say 2.1 to 2.2 would be boarderline extortion.

It is usual within the industry to discount new versions for previous version owners. Indeed in some cases updates are provided free of charge within a whole version number.

So for instance, having bought a plugin for 2.1, I'd expect it to be updated free until Nop hit 3.0. Remember the author is having to do this work anyway to ensure the plugin works with the latest version so they can continue to sell to new customers.

I do feel this matters as it reflects badly on the project if people are being taken advantage of.

Your thoughts.

Like you say, it depends on the effort involved.

If all the author does to upgrade from 2.7 to 3.0 is change to version number than
it should be a free upgrade.

But lets say, the plugin is constantly improved, then an upgrade from 2.6 to 2.7
shouldn't be free because the author did spent a lot of time.

If a plugin is improved constantly, I think it's reasonable to have a time-based upgrade period.

If you buy a plugin you get X months of free upgrades, no matter what version of nop because
the plugin is improved constantly (eg. gets more features, goes from v1.0 to v1.5 and works
in nop 2.7, 2.8 & 3.0 for example)

agree, depends on the effort.
if just simple upgrading, it should be free.