My sister found a bunch of old baseball cards that her no-good fiance left at her house. She has a huge binder full and knows online drugs nothing about baseball. How would she go about finding their value without looking them up one by one on ebay? What shouldn’t she do?

im just looking to buy things for next season baseball pharmacy online express is to expensive any cheaper web sites?
baseball express is to expensive im just trying to buy all new things like cleats glove bat etc.
baseball express and ebay is always a possibility but im just trying to buy all new things like cleats glove bat etc. any other cheap websites like ebay?