On Erev Pesach I asked a friend to buy for me a bottle of semi-dry non-mevushal wine which I would use for Arba Kosos. He later dropped off the bottle at my home, and I went round to him to pay him for the bottle. Even before I paid him, I noticed that in fact it was Mevushal, but I decided to keep it. I would have liked to have the מעלה of non-Mevushel for the seder, but too bad, I didn’t have the time to switch it and this bottle was also 100% ok.
After yom tov, somehow my friend chapped the mistake and he sent round to me an envelope with the money inside. He said the rule is לתקוני שדרתיך ולא לעוותי, you asked for non-mevushel and I made a mistake, take the money back. I insisted that I was happy with the bottle he bought and it wasn’t even b’dieved, but he is not convinced. Please can you clarify the halacha for me.
Your friend does not have to pay you for the wine, even without getting into the halachos of shlichus, you used the wine, so even if he does pay you for it, the bottle is then his and you will have to pay him for it. Besides you did notice it before you paid for it, and were mochel it, so this rule will not apply.