Hello, i have collected my little pony's since a kid and so did my sister. My parents did not have a big house so some of the pony's were never opened depending on which one of us did not get the good flip of the coin. My parent's kept them in their attic intel me and my husband moved into our own house. Some of the boxes they were in have a yellow tint to the clear plastic of the boxes that were not opened. How would someone go about cleaning the boxes without ruining their value? Can i open the boxes and make sure the pony's are ok in the box or will this ruin the value as well? I have a lot of questions because i have over 100 g1 and some g2 pony's and want to make sure they are in good condition because I would like to start selling them if possible. Thank you everyone for any suggestions or help.