It is not permissible to accept money in return for acting as guarantor for someone

Selling old coins for more than their face value

It is not permissible to sell gold for cash with a delay in payment

Should he cancel the investment certificates after a fatwa was issued stating that it is prohibited to invest in them? And what is the ruling on previous profit?

Loans with interest for students and recent graduates

What is the ruling on renting out space for installation of an ATM belonging to a bank?

Ruling on buying an account on Amazon that already has a certain amount of credit, in return for more or less than what is already there

Can he sell his house to someone who he knows is going to buy it with a riba-based loan?

Rulings on rewards for having a current account, if the reward comes after the customer withdrew all the money from that account

They give employees a share of the profits, and give no option but to have them deposited in a riba-based bank. What is the ruling?