I have just recieved a fendi bag i purchased off e-bay that was advertised as an authentic brown spy nappa bag .. new with tags, serial number, and care cards.. The bag arrived on time. There was a serial number, but the finishing of the bag is not 100%. I dont know whether i am being picky or whether it is a fake. I tried googling the serial number, and i think it may be fake. The serial number is:a497663 PLease advise. What should i do? How can i be certain that i have not been cheated?