When is Istikharah (guidance prayer) Du`a offered, before Tasleem (saying asalamu alikum warahmatu allah wa barakatuh to end the prayer), or after it?
It is offered after Tasleem.
What is the ruling on paying a sum of money to Saudi citizen in return of having Saudi residence? It is worth noting that this transation is labelled as a "worker's visa" but I am not going to work as such only to facilitate having it?
Allah The Almighty Says (What means): "O you who have believed, fear Allah and be with the truthful" [At-Tawbah/119]. False statements contradict truthfulness, and it is not permissible to write them. A Muslim has the right to live in any Islamic country, and those who prevent him will be accountable before Allah about their action and the justification for the prohibition. And Allah Knows Best.
Is it permissible to make up missed prayers at the times in which praying is disliked?
All perfect praise be to Allah,The Lord of The Worlds It is permissible to make up missed prayers at any time even that in which praying is disliked. Absolute supererogatory prayer is forbidden to be performed at the times in which praying is disliked, and this also applies to Ihram and Istikhara prayers. However, there is no harm in offering prayers in Mekah during those times. And Allah Knows Best.
Is it disliked to clip one`s nails at night, and to burn them afterwards?
It is recommended to bury hair and nails that have been removed and to conceal them in the ground. As for burning nails, we have not found any specific prohibition against it, but adhering to what is supported by evidence—burying the nails—is preferable. And Allah Knows Best.