Current the s23+ is listed at $750 on the Samsung Shop mobile app. Various trade ins are listed at $200, but if applied yield a total of $600 for the phone… the way they justify this is that because the phone is originally $1000, and it’s being discounted by 25%, they take $200 off of the original price of the phone before applying the discount. I.e. ($1000-$200)*0.75=$600. So your trade in is really only valued at $150 by Samsung.
In my opinion it’s shady to advertise the $750 price (after the discount) but NOT advertise the trade in value after the discount.