Is it possible to copy of planned cost to estimate cost in cost TAB by defined value category-wise?

Hello ,

My business want to copy planned cost to estimate cost by value category wise.

for Eg. if there are 4 value categories are defined in system.

1.maint.material

2.labour charge

3.Ext service cost

4.others

and if i want system to copy the planned cost to estimate cost by above category-wise every time when i SAVE the order before releasing the same.also once i release the order this functionality should stop copying the values, is it possible?

please reply.