MONEY and JAIL (mostly)
21 for California.
no
You can read more on the California DUI penalties on the official California website for law enforcement. They provide you with the required information for DUIs.
In general, any felony makes you inelligible to own a handgun.
You need to consult with a lawyer for a legally correct and current answer.
I don't know about California, but in most states there is no official gun registration. You can carry a handgun in California if you have a California handgun permit, but I understand those are hard to obtain in some counties.
No.
What is concealment of information?
FineImprisonmentDisqualification from OfficeRemoval from OfficeDeath
concealment of property
if a gun has a threaded barrel, (required for a silencer) it is classified as an "assault weapon" and is illegal in California.
I used the tall grass for concealment.