How to cancel the ownership of the house?

Call for legal experts urgently! Thanks in advance! Qin, a factory worker, has a good relationship with his girlfriend. Last year, they decided to buy a commercial house to get married. They took a fancy to an auction house of about 350 thousand in a certain district and decided to buy it by mortgage. At that time, Qin's parents paid a deposit and down payment of 6.5438 million yuan, but the woman didn't pay a penny, only verbally promised to bear the future monthly payment. Because of his affection for the woman, Qin listed her as the "* * * owner" of the house when buying a house. The two have a good relationship so far, but they still haven't gone through the marriage formalities. Due to the reform of the factory system, Qin was laid off at the beginning of this year and lost his fixed income. So far, he hasn't been able to find a stable job, and the woman has suggested that she can't afford the monthly payment. In this case, how can the property right of the house be completely owned by Qin, so that the uninvested woman is no longer the owner of the house? Qin's family doesn't want to check out, because the loss will reach more than 50 thousand yuan. However, while the woman is still "the same owner", she is afraid to pay more to buy a house for fear that the woman will divide the property. Asked about the opening of the house, the house said that the way to minimize the loss is to go through the formalities of change, but it must go through the Housing Authority. Later, I asked the Housing Authority, and the Housing Authority replied that "you can only check out first" or you can only deal with it as a "transaction", but it will take two years and pay a lot of taxes to do it as a "transaction". I really want to know whether the statement of the Housing Authority is reasonable and legal. Originally, it was jointly owned by two people. Can voluntary transfer to a person's name be considered a transaction? Is there a charge if it is a gift? In addition, it is suggested that the two people sign an agreement, and the woman voluntarily gives up the ownership and then notarizes it. Without consulting the notary office, the Housing Authority said that it could not be notarized without the real estate license. Is it true?/You don't say. If this is the case, it will be stuck in a "dead set" because it takes time and money to run a real estate license. After the real estate license is completed, the woman's name will inevitably appear on the real estate license in the form of * * * *, which is what the Qin family is most worried about. But if there is no real estate license, can it be notarized? If the agreement signed by both parties cannot be notarized, is it legally effective? Can a lawyer notarize the agreement after signing it? Note: At present, the relationship between Qin and the woman is still good. At least on the surface, the woman expressed her willingness to give up the house, and she fully admitted that she had never paid a penny.