PayPal is a necessary evil, in some cases, but I also avoid it when possible.
I use Stripe to process on-site payments, and I transfer funds in some cases with Payoneer, but I still have to use PayPal sometimes.

There have been two instances of fraud where PayPal basically supported a seller I was trying to get my money back from.
In one case, the seller clearly had a giant 30-day refund guarantee, where I downloaded their software, and it was clearly installing viruses, but when I made a fraud report, it was like PayPal closed the case as quickly as possible, without refunding the money.

I've probably lost $1.5k just as a result of bad support from PayPal.
The secret is you have to call them on the phone, and dog them every single day like a madman, if you can't get a proper ruling from the online system.
Like a lot of support systems, they make it very tedious to make reports, and then once you do that, it often seems like no one reviews your reports. (LoL)

If I could go back, I'd probably call them on the phone more frequently, and if that didn't work, I'd probably look into making a report with the Federal Trade Commission (FTC).
A bigger problem than PayPal, though, is just trusting the wrong people, and then trusting that PayPal will protect you against those people.

If there's any doubt... just don't bother making the purchase.
Never spend money that you aren't prepared to lose. (ugly truth of IM)