The girl's mother told the boy that she wanted to borrow money to buy a house and asked the boy how much money you have now.
Are this boy and this girl boyfriend and girlfriend? If not, mother can't ask the boy how much money you have. What he means is that when you two get along together, you have to prepare to buy a house before you can get married. At least you have to have some deposits as a down payment before you can borrow money to buy a house.