The ruling on selling goods on installment, and the ruling on selling them for two prices, one immediate and the other deferred

Question:
May Allah reward you. The sisters, Ibtisam and Qamar, and Muhammad 'Abd Allah Maqrum from Yemen, Abyan Governorate, have two questions. In the first, they ask: Is it permissible to sell something for three hundred riyals immediately and three hundred riyals by the end of the month? Is this considered riba (usury or interest)?

Answer:
It is permissible to sell an item for an installment price, praise be to Allah, for an installment price with an immediate installment and a deferred installment, or for deferred installments. However, if the intention is that they are selling the item for two prices, immediate or deferred, deferred for such-and-such or immediate for such-and-such, then this is a sale that has not been concluded. This is a sale that has not been concluded because they have not decided on one of the two prices. And the Messenger (peace and blessings be upon him) said: Yes.