Ruling on selling goods on installment with an increase in the price

This is a letter from Abdullah ibn Ali from Jizan. He says in his letter: I wanted to buy electrical appliances for my house so that I and my children could live in it, but I did not have any money. So I went to a man who had money, and he said: I will buy them for you. He bought them for seven thousand, five hundred, and forty riyals and sold them to me for nine thousand and four hundred riyals on a deferred basis, to be paid in monthly installments of one thousand riyals each month.
The Shaykh: Repeat the question.
The presenter: The question says: I needed electrical appliances and I did not have any money.
The Shaykh: Appliances?
The presenter: Yes, tools, I mean.
The Shaykh: Yes.
The presenter: And I did not have any money, so I went to a man who had money, and he bought them for me for seven thousand, five hundred, and forty riyals and sold them to me for nine thousand and four hundred on a deferred basis, to be paid in monthly installments, each installment being one thousand riyals. What is the ruling of the Shari'ah in this matter?
Answer: If the one who sold to you took possession of these appliances and tools and owned them, and then sold them to you afterwards for a known amount on an installment basis, there is no harm. But he does not have the right to sell them to you before he owns them. If he knows that you want them and that you need them, he buys them and takes possession of them from their owners, in his house or in the market or in any place, transferring them to him from the seller's ownership, and then he sells these tools to you for a known price on an installment basis, such as so much each month, or so much each year, there is no blame on him. Yes.