say i have $500 left in my account and i want to withdraw $800 to my bank account. will it work? i have verified paypal account.
Quite obvious you can't. You can only withdraw what you have current balance(cleared ) in your account.
how about if i have credit card attached? i know they will charge credit card for sending money (incase sending funds insufficient) but is that possible for withdrawal?
Nope, that is illegal actually because that would be considered a cash advance but wouldn't be treated as one.
Yes, cash advances is prohibited and you cannot use paypal for that purpose. Besides you cannot use Paypal to pay yourself. However if you really need the money, you should be able to use your credit card in an ATM machine to do a cash advance that way. However, it is not free and if the way the credit cards works the same here as in Singapore, your interest billing would start on the day you do the withdrawal. https://www.paypal.com/us/cgi-bin/webscr?cmd=xpt/UserAgreement/ua/USUA-outside#restricted-policy