Is it enough to say Tasbeeh (Saying Subhaana Rabbiya Al-‘Atheem during Rukoo`, and saying Subhaana Rabbiya Al-A‘laa during Sujood ) once, or twice during Rukoo`(Bowing in prayer) and Sujood (Prostration)?
All perfect praise be to Allah, The Lord of The Worlds Yes, saying Tasbeeh once during Rukoo` and Sujood is enough, provided that the worshiper`s attentiveness of the heart isn`t undermined during each. As regards the recompense, it depends on the number of Tasbeeh. And Allah Knows Best.
How does the person praying perform the prostration (Sujud)?
Praise be to Allah, and peace and blessings be upon our Master, the Messenger of Allah.
It is an act of Sunnah for the person praying to descend for prostration (Sujud) by placing their knees first, then placing their hands on the ground, and then placing their nose and forehead simultaneously. It is obligatory that the toes of the feet be on the ground, directed towards the Qibla. And Allah the Exalted knows best.
Should a prayer performer who forgets to offer the middle Tashahod (saying ash-hadu anala ilaha ila-alah) offer Sujood As-Sahw (prostration of forgetfulness)?
He/she should offer two prostrations of forgetfulness at the end of the prayer. And Allah Knows Best.
What is the ruling of Islamic Law on obtaining financing from Islamic banks by bringing invoices in prior arrangement with the seller, then taking the cash after the financing is approved — with the purpose of settling debts and buying a car?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah ﷺ.
It appears from the transaction described that its underlying purpose is to obtain cash through resorting to a legal artifice (ḥīlah/tawarruq-style trick), and it is not permissible to engage in such trickery or to coordinate with the various parties merely to obtain liquidity. This is because such artifices bring the sale closer in reality to a ribā-based (usurious) transaction, even if it outwardly appears otherwise.
The Prophet ﷺ said: "Do not commit what the Jews committed, thereby making lawful what Allah has made unlawful through the flimsiest of tricks." This was related by Ibn Baṭṭah in his book Ibṭāl al-Ḥiyal (p. 47), and many scholars have graded it as ḥasan (sound/acceptable).
We have already explained the impermissibility of engaging in such deceptive dealings with Islamic banks in Fatwa No. 516, so please refer to it. And Allah, the Exalted, knows best.