Re: linking Paypal to a bank account, I strongly advise opening a new account, not connected to your other accounts*, to link to Paypal. That way if Paypal takes it into their heads that something you're doing is wonky, and they come and take money back from you, they can only take what's in the specific linked account. Meanwhile, you can transfer funds regularly from the Paypal-linked account to the other, non-linked account(s), leaving little or no money in the linked account, so Paypal can't actually hurt you that way.

(I've seen this happen to two different businesses, both legitimate, so even though many businesses never have a problem with Paypal, I think it's best to take precauutions. We handle our own Paypal account this way, FWIW.)

*If your Paypal-linked account requires manual funds transfers to your other account, rather than being set up for money to move automatically between it and your other accounts (such as an automatic funds transfer to prevent overdrafts), you're safe from Paypal being able to take advantage of said automatic funds transfers to take as much money as they want.