Charity

No problem but he must pay zakat if the savings reaches the level of nisaab and one lunar year passed by.

It happened at the time of Omer Ibn Abdul Aziz because he was fair and just.

Yes

The reward will be for the person you giving for.

Whatever good you do, Allah will reward you even if you give half a date to a poor man

It is better to give your family members.

There is no comparison between helping a needy Muslim and helping a Christian. It is an obligation to help a Muslim.

If he is a needy Muslim, it is permissible to give him. not praying with the congregation doesn’t mean he is not Muslim or that he should be deprived of charity.

It is permissible to give charity to your needy close relatives.

  If you give them, Allah will reward you. But if you strongly believe that they are not needy and they are professional beggars, you shouldn’t give them and look for real needy people and give them sadaqah