BRAND & MODEL
A bag of a high-end brand will value more. The worth of an iconic model of a popular brand will be higher than a model which is not Limited Edition.
Various types of leather bags are available, some costlier than the others. So the value of a bag also depends on the cost of the material.
A bag's condition is a key factor that affects its value. Any wear & tear like scratches can impact its worth. If your bag is damaged, it will fetch a lower amount.
The quality of your bag definitely will impact its worth. Good quality is directly proportional to higher value anyone can pay for it.
Accessories attached to your bag too impact its value. All the accessories intact will make it look attractive and increase its worth.
PROOF OF PURCHASE
A receipt is essential to prove that the bag is original and will also reveal its price at the time of purchase. Its original box and any certificate will add to its value.