How Much $ to give at Christening

Hi

I am going this Sunday to my cousin's first child's christening.

How much should I give them?

Do I need to cover the plate also at the hall? They are having it at the same place they got married at 5 years ago.

TIA.

Somewhere between $50-$100 is more than appropriate. You shouldn't have to cover the cost of the plate - it's not your problem where they decided to have it.