try reading PayPal policies here:

https://www.paypal.com/au/webapps/mpp/full-sitemap

and here:

https://www.paypal.com/au/webapps/mpp/ua/legalhub-full

and here:

https://www.paypal.com/au/webapps/mpp/ua/useragreement-full#int_17_Reserves

and section 4.4 here:

https://www.paypal.com/au/webapps/mpp/ua/useragreement-full#int_4_Important_things_you_should_know

and here:

https://www.paypal.com/au/webapps/mpp/ua/useragreement-full#int_12_Recovery_of_payments_owed

and section 16.2 here:

https://www.paypal.com/au/webapps/mpp/ua/cfsgpds-full

I am making it easier for you. Now, do your own homework and go and read ALL of these links I have provided.