Preowned phone is always a nightmare. You may end up with paying restock fees even for no fault of yours.
My personal experience says, the phone had few minor scratches but clean. While examining closely , I noticed a big gap at one of the screen. Certainly that is a defect. But when I explained the store manager, they initiated the returns but charged me $35.
You can definitely try your luck but be open to pay the restock fees.