for the EU (maybe also US not sure please check) payments you may be better off using www.transferwise.com services. They are great.
I think that the PayPal is still one of the cheapest solutions. If you use bank transfer, the bank will charge you for the transfer in different currency (I assume your bank account is in EUR, his in USD) and will use the exchange rate that suits the best... the bank.
I did this recently (paid from Belgium a Czech freelancer) via bank transfer and the exchange rate + all the fees cost something like 7% of the amount...