ninadepalma That's an excellent question @ninadepalma! In my case it all depends on the client. Sometimes they pay the transfer fees without hesitation and sometimes they want me to cover the fees. I always account for transfer fees when I'm working with agencies and they're built into my rate.
I'm not sure what's the best payment system is because I've been working with PayPal for so long, I don't even want to change it, but I've heard there are some better alternatives with lower rates.
What I recently did is developed a online portal for my clients where they can view their estimates and pay their invoices instantly by paying directly from PayPal or their Credit/Debit Card. That way there are no transfer fees because they're paying an invoice instead of sending money manually, plus it secure, fast and easy. Oh, and it also feels great when clients pay BEFORE the project starts.
But I guess this is possible only with direct clients.