How to set up depreciation key in difference scenarios

Dear experts,

we have 3 specific scenarios:

1- Asset under 30 Mil and we dont want to run depreciation for it.

2- asset Under 30 Mil and then we transfer from another asset then APC up over 30 mil. we want to run dep but till APC = 30mil asset will stop depreciation

3- Asset over 30mil but we retire partial then APC <= 30mil and we want to stop depreciation

Do you know how to set up depreciation key based on these scenarios?

thanks all.