I earned some money outside of my country in USD currency (foreign currency). My friend who lives in my country wants to buy some good from online shopping websites so I agreed with him to sell him the amount of money he needs (because we can't have foreign currency in our country) and we agreed about the exchange rate which is higher than the official exchange rate.
I'm considering this as I'm selling a foreign currency against a local currency.
Example: in reality 1 USD equals to 136 DZD. We agreed to sell him 1 USD for 140 DZD. Because I'm considering the USD as good I want to sell. I know I can withdraw it for 136 USD but I wanted to use it one last time to gain a small amount of money by doing this. I don't have any intention to impose an interest. Is this considered as Riba (usury)?
One more detail I wanted to add is: I agreed with my friend to receive the money few weeks late as long as the delay doesn't affect what we agreed about so if he purchased a product for 10 USD, he will pay me 1400 DZD even if he pays immediately or few weeks late. I agreed about this because nowadays people can be in a situation where they can't afford the money immediately, so I had good faith by agreeing about waiting for the payment few weeks late and my intention was not to impose any interest. This is because the products he is purchasing gets available in short amount of time with 10% or 20% of reduction so the website cannot wait for him to have the money after few weeks because after few weeks the 10% or 20% of reduction on the product he wanted to purchase will be gone.
Basically, I'm using my money because he don't have money outside of the country and we agreed about everything in a fixed price which means even if today 1 USD will be 137 or 135 DZD, he will pay 140 DZD by USD. Is this considered as halal? please note that I'm considring the USD as a product I'm selling without applying any interest no matter what happens.
I know the requirements should be "hand to hand", so my friend is giving me the money hand to hand. And the second requirement is "with no delays". In this case there is a delay but that delay does not affect the amount of money that was paid at that time and it doesn't affect the amount of money I will be receiving since we agreed about that and there is no interest applied to the transaction.
Like I said, it was with good faith from me to make it easier for my friend to use my service (giving him higher fees is the fee of the service I'm giving when I make the purchase for him) and then he pays me when the money becomes available for him and I didn't intend to take advantage of him at any means apart from selling him the foreign currency for a higher price.
I hope this is not considered as haram.