This is not possible at this stage within HubSpot, I'd recommend upvoting this Idea in our Ideas Forum regarding this. You can also subscribe to the idea (Options > Subscribe) to get notified if the status changes.
Will we have calculated properties to line items too?
yeah, there not available, but would be amazing if could be available. Why is not available?
I need to use an API to change customized properties of line items and is very painful because we always reach the request limits. That makes all the process of the sales team be very slow and confused.