You must be a Christian to get married in church, because this is a marriage established by God (Genesis 2, Old Testament, 18-25), so Christians should witness before God on the wedding day and get God's blessing. According to the teaching of Christ, premarital sex is wrong, and believers are no exception. These are all sins, so if you want to hold a wedding in a church, you must believe in the Lord before being baptized, and ask God to forgive your sins. And your other half must be a believer, otherwise the priest will not bless you and the church will not accept you. These are some basic conditions. Church weddings are free, because this is God's home. God's grace is given to you for nothing. As long as you are willing to accept it, money can't buy it, because God is not short of money. May the Lord Jesus bless you