>>11554147
I keep all my cards 'resealable' so when I have one I want to open I use this method. I use a sharp boxcutter to cut the outermost (not all the way through) edges in between the plastic and cardboard of only the sides and bottom of the plastic case. The top will not be cut and will stay attached.

After the edges have been cut all the way around, find an area close to one of the corners to 'pierce' the tip of the razor blade through the printing on the inside of the case. Only a small opening needs to be made, enough for a pick (toothpick can work) to slide into.

Then push/roll the pick towards the corner with the tip facing that direction. This pries the plastic off while preventing it from pulling up excess printing on the inside. Do this on the rest of the sides until the case can swing up to let the car out.

The opened case can be glued back shut with an invisibe gluestick. It doesn't leave the case looking 100% unopened, especially if theres colored printing near the case borders. The 'pierce' part is the hardest part to do with minimal damage, so it takes practice to master this technique.