Must a wife know the monthly income and money in the bank, or any wealth of her husband when the family has a good life?

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

It is not compulsory for a husband to inform his wife about his salary and other properties. If a wife thinks that such an inquiry may damage her marital life then she should not raise such questions, particularly if the family enjoys a happy life as you mentioned in your question.

Allah knows best.