Good accounts make good friends.

Written contracts and reciepts are the ways how trade is done. Period. Yes, this prevents double requirements but it also prevents awkward questions like "Did I repay you the money allready?"

Also keep in mind that mixing money and friendship is not a good idea at all. Reasonable people know that. That's why you wrote and signed the contract in the first place, right?

In other words, the only people insulted by demanding written contract/reciept are the ones who wanted to abuse your trust in them. Reasonable people will check the reciept and sign. Good friend will welcome that.

Just give them the reciept with appropriate wording (official if they like the official style, something creative if they like informal jokes, etc).

True businessmen are really uncomfortable when "friendship" and "love" are mixed with the business and when the terms are not clear. Maybe your friend is preparing the reciept too.

Good accounts make good friends.

Written contracts and receipts are the way how a trade is done. Period. Yes, this prevents double requirements but it also prevents awkward questions like "Did I repay you the money already?"

Also keep in mind that mixing money and friendship is not a good idea at all. Reasonable people know that. That's why you wrote and signed the contract in the first place, right?

In other words, the only people insulted by demanding written contract/receipt are the ones who wanted to abuse your trust in them. Reasonable people will check the receipt and sign. Good friend will welcome that.

Just give them the receipt with appropriate wording (official if they like the official style, something creative if they like informal jokes, etc).

True businessmen are really uncomfortable when "friendship" and "love" are mixed with the business and when the terms are not clear. Maybe your friend is preparing the receipt too.