I bought a house with my friends (friends are just good friends in the mall, same sex). Now I have bought a duplex building in a residential area, and I can enter the house alone upstairs.
Housing sales must go through the relevant housing transfer procedures of the Housing Authority. The contract you signed privately violates the relevant laws and regulations (do you want to avoid paying the relevant fees? ) So it is an illegal and invalid contract. In case of dispute, this contract has no legal effect. Fairness alone is useless. Only going to the Housing Authority for legal transfer procedures is the only way out.