That depends on many factors all listed in Paypals buyer protection policy for you to read so you can risk assess your transactions. Legal (bottom right of Paypals pages) > user agreement > buyer protection.
MAKE SURE ITS NOT ONE OF THESE >>>
Chinese Web Sites or on Social Media ads easy to spot (once you know the below signs) so buyer beware.
1. No return address on the returns policy............thats because the site will look as if its in your country (where they despatch goods from) BUT they will ask for returns to go back to China (returns depot) at a shipping cost nearly always more than the item is worth. 2. No contact telephone number............if you click on contact the most you will get is webmail or an email address. 3. No company address information. 4. Great looking items at bargain prices that turn out to be tat.
Advice is voluntary. Kudos / Solution appreciated.