Is it permissible to give money to a property owner for the purpose of furnishing apartments in exchange for guaranteeing the return of the money and the rent of the furnished apartments for six months as profit?

It is not permissible to give money to the landlord to furnish the apartments, with the understanding that he will guarantee the return of the money in addition to the rent of the apartments. This is a usurious loan, which is forbidden and considered one of the major sins.