According to Pay Pal's website:
This is if you set yourself up as a Paypal merchant. Looks like a lot of these such solutions (Paypal has something like 6 of them), it's $20/month.
However, looking at the finer print, I'm guessing that the place that wants to pay you has Paypal. In that case, except for the "Additional Payment" Option, their customers (I guess that includes you) do not need to have a Paypal account.
But it may not hurt to have one, anyway, as it can come in handy. I believe that it would take the place of a direct deposit but I've never actually been paid by Paypal; I've just paid out from it.