Entering Nepal without a return ticket (Kathmandu)

Hello everyone!

I will arrive in Nepal in August, and this time I will be travelling without a return ticket. Because my plans after Nepal are still uncertain...most probably India by road.
So I will fly with Turkish Airlines from Argentina, via Istambul, and then Kathmandou.
My question is if not havin a return ticket from Nepal can be a issue at either Argentina, Turkey or Nepal airports... the people at the airline tell me usually you can have trouble at airports if you don´t have proof that you are going to leave the country you are visiting... but I don´t know if Nepal is the case.

Does anyone have a clue about this??

Thank you very much!

Juan