How to set spawn or add times on commands for different gm levels

[Found]

How can I set my commands like this (in core) or any other way

GM Level 1 .char add 20 items every hour .gob sp only 5 per 5 min
GM Level 2 .char add 30 items every hour .gob sp only 10 per 5 min
GM Level 3 .~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

etc..

how can i do this for 8 gm levels in the core or any other way?

Thanks for any help
and as always
thanks in advance

-L0st