Locking an estimate from being edited after it's been approved / declined; would be advisable. Similar to a invoice being locked.

If a change needs to happen; then the estimate needs to be either cloned or UN-Approved/Declined.

We run into situations where a customer may approve an estimate; and then someone goes and changes / updates items in the estimate after approval... making it very difficult to track changes.

This would be helpful.

There seems to be a somewhat similar request here:

http://feedback.repairshopr.com/forums/165658-general/suggestions/14765361-lock-or-freeze-estimates-and-invoices-from-being-e