For money safe what colour better?

Safes are always sold either black, grey, gunmetal colours. No safe that is bright yellow, red , green or blue.l Even if want such colours.... go spray paint them

So can take black or gray?

Feng Shui does not micro manage colours such as black or grey for safes.

The hong bao for stove and drawer need put how long?

hong bao at stove suppose to use up. For the drawers, it is like depositing money ... into the house. Withdraw - if move-out. Else Permanent