Is it permissible for the wife to stipulate before marriage that her husband marry three women after her, and that she fast one day and break her fast one day, and that she work in Qur'an memorization and in a women-only center for introducing Islam?

It is permissible for each spouse to stipulate conditions to their partner, provided these conditions do not contravene Sharia (definition). If they do, they become null and void. If the conditions are permissible and do not violate Sharia, then fulfilling them is obligatory, as Allah Almighty says: (O YOU WHO HAVE BELIEVED, FULFILL [ALL] CONTRACTS) [5:1], and the Prophet, peace and blessings be upon him, said: (The most deserving of conditions to be fulfilled are those by which you make intimate relations lawful). Therefore, a condition by which intimate relations become lawful and whose benefit accrues to one of the parties must be fulfilled. Conditions in marriage are divided into three categories, one of which is obligatory to fulfill, namely, those whose benefit and advantage return to one of the spouses, such as not taking her out of her home or country, or not traveling with her, or not marrying another wife.

Regarding the wife's condition that her husband marry three wives after her, it is a strange condition but the husband is obligated to fulfill it if he agrees to it, or they can agree to cancel or alleviate it. She can also waive it after the contract. It is advisable to specify a timeframe for fulfilling this condition. Nevertheless, such a condition is not recommended; rather, marry as other women marry.

As for stipulating fasting, it is not recommended, and none of the righteous predecessors did so. Abdullah ibn Amr ibn al-Aas obliged himself to fast every other day, but then found extreme hardship in his old age.

Regarding a woman's work, Sharia does not prohibit it as long as she adheres to the Sharia guidelines.