Sale with performance increase or without?

Hello to each other, so I have a Seat Leon SC FR 1.8 TSI 6-speed switch and I would like to sell this in the near future because I ordered a Cupra. The vehicle currently has a performance increase by software to 220 hp and I just don’t know now if I should put it away or leave it on it, because the tuning is not registered either. If I remove it I will anyway say that the vehicle had a tuning because I don’t want to have problems late I hope you can help me.