Template Store Update

i would like to start selling a template on the store but i cannot reach to understand how update/upgrade to my template should works.
What i mean is that i create a template and start selling it.
After some times i discover a BUG and a would like to release and update to my original template.
How this works ?
The customers must buy the template again ?
Or i can/must give the update for free?
And what about if i add some functionality and make a BIG upgrade ?
Is there a “versioning” tool or similar ?
Thanks for your reply

If someone purchases a template, that’s the version they get in it’s current state. If you make changes and update the template, I believe they can still redownload it for free, since they have already purchased it. But, it will not update any existing projects that originated from an earlier version of that template.

Once someone downloads a template and starts using it to build out their project, they will have to work out the bugs and any upgrades themselves. Templates are only meant to be a starting point to a final project. If you want to support them and their project further, I guess that’s up to you at a cost that you feel is fair. You are not obligated to provide continual updates and support to their projectonce they have made a purchase.