Does the clipping of nails nullify ablution?
No, it does not, and it is preferable to wash the hands afterwards.
Is washing the private part after urinating (Istinjaa`) a condition, and is it done with water and soap, or with water only?
Istinjaa` is obligatory for removing impurity, and it can be done with toilet paper, or a stone, or water. It is preferable to do Istinjaa` first with paper, or stone, or the like, then to wash the private part with water until making sure that the impurity has been removed. Using soap is not a condition, but there is no harm in doing so provided that it is washed off with water. It is also permissible to use either water, or paper if impurity is removed by any.
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.
I wish to purchase an online account (a gaming account), and its ownership will be transferred to me. However, my friend will purchase it on my behalf, and I will repay him in deferred installments with an added profit margin to account for the installment sale. What is the ruling of Islamic Law on this transaction?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah.
The ruling on selling electronic games depends on the ruling of the game itself: if the game is permissible, then selling it is likewise permissible. However, if the game contains Sharia violations that render playing it impermissible, then selling it in that case is neither valid nor permissible. Therefore, we advise the necessity of reviewing the Sharia guidelines for electronic games set forth in Fatwa No. (3369).
Accordingly, if the game is permissible, a person may purchase it, take legal possession of it, and subsequently sell it in deferred installments for a price higher than its purchase price. The General Iftaa' Department has permitted dealing through Murabaha, while emphasizing the necessity of observing the Sharia conditions required for this transaction; please refer to Fatwa No. (2861). And Allah Almighty knows best.