Must a woman build a mosque after retrieving the money she paid to build a mosque, and does she bear a sin for using the money for her personal needs, and is there a difference between using the money for very necessary or unnecessary needs?

If a woman utters an explicit or implicit statement of waqf (endowment), or performs an action indicating waqf coupled with intention, then the property has exited her ownership and become a waqf, which cannot be revoked.

Even if the waqf property has not physically left the endower's possession, it becomes effective immediately upon endowment.

Therefore, the woman must repent to Allah for revoking the waqf and compensate for whatever she has spent from it, as need does not justify revoking a waqf.