Conditions for the validity of Nikaah

Q: For a man to marry a second wife, does he need to ask permission to his first wife?

Q: In my area the Shariah is not applied to its extent. My question is regarding marriage. There are many so called Muslims getting married according to the customs of this area which is not in compliance wih Shariah. People roam freely to choose and meet there life partners instead of the Shariah compliant way. Will these marriages be cosidered as Legal according Shariah?

Q: Does Islam allow one to marry to non muslim or muslim girl just to seek visa settlement and make a deal with her and pay her for that. After getting the visa the matter is finished. The marriage is just in papers.

Q: My question is can I do marriage just in papers not actually with proper intentions nor physically. Also the female knows its just for papers not actual marriage. Its just to gain visa. I consulted with a lot of people most of them said if you are not betraying the person its fine Islam allows to make secure your future and for a better life. The example in my mind is about our prophet Ibrahim (Alayhis Salaam). He said his wife is his sister. Its just to obtain UK registrar office certificate and to put it in file but to make a strong case you have to do nikaah as well. This all is in papers. Only I and her know about this that this is just for visa.

Q: Is it permissible for a women to have a contract before marriage stipulating that the husband cannot take another wife for five years. If it is permissible and the husband agrees and violates the agreement by taking another wife, does the wife have grounds for a khula?

Q: Is it permissible for a woman to stipulate before marriage that the husband cannot take another wife for a certain amount of years? If the husband does take another wife, does it nullify the nikkah?

Q: My cousin and her fiance' did ijaab and qabul (proposal and acceptance) without a khutba in the presence of two females and one male (the first female is my cousin i.e my brothers wife and the second female is her cousin and the boy is also her cousin). Is this nikah valid?

Q: A woman got married to another man right after her divorce without completing her iddat. What is the status of her marriage to the other man. Is the nikaah valid?

Q: If a boy tells a girl isn't you are my wife infront of two baaligh men and the girl replies yes then are they regarded to be married?

Q: I am writing this email because someone known to me is facing a strange situation and have insisted me to ask you this question. He is already married but have contracted nikah with someone else as well. However, when he committed the second lady about nikah, there wasn't any witness to that. Soon after that promise (or whatever you call it) the lady called her father and told about it. Father called the person and showed his agreement to her daughter's decision. Then they publicized this agreement to their family members. The first wife of the person called the lady and discussed various matters about her husband's marriage with the lady. Subsequently, the first wife announced that in their family. everyone accepted this decision. However, till date no formal document has been signed.

Now a million dollar question is about validity of this nikah. Please comment in the light of Quran and Sunnah.