Missing items from package - Will I get a refund?

[Plarka]

I bought a set of math books and dvds from someone on facebook marketplace.  I received the package but one of the books is missing and also the DVDs are missing!  It doesn't look like the package was tampered with, and it doesn't look like another book and DVD case would have even fit in there. The seller claims she sent them all and showed the receipt saying the weight was almost 8lb so they must all be in there.  Will she win the case because she has the receipt saying the weight?  Does that mean anything? Will they believe me because I have photos of the package with only two books in it?  I think she might have gotten all the items weighed, and then once she paid and got the mailing sticker, took out the main book and DVDs so she can sell them again, and only then sealed up the package. She was very quick to keep pointing out the weight on the receipt, which she sent me when she sent the package, but there was never a picture of the package.  Do people do this??

[kernowlass]

@Plarka 

You can certainly open a paypal dispute for item received but not as described BUT if you win paypal normally tell you to return everything you received back to the seller for a full refund. This is done at your own expense and trackable to prove delivery back to the seller but you may be able to claim some or all of those funds back if you have activated the 'return shipping link' in your paypal account.

Paypal does not get involved in part refunds or part returns which is why they state everything must be returned for a full refund (only if you win).