It won’t be problem get to your hotel or guest house from Kathmandu airport even if you didn’t arrange transfer, as there are plenty of taxis waiting for you. But how much does it cost? The first price you’ll hear will be about 1000 Nepalese rupees (NPR). It doesn’t sound much if convert that amount to Euros or US$, but for taxi drivers it will be a fortune. There is no fixed fee, so if you don’t like price, just go ask another driver. It should cost 200-300NPR max to get to Thamel from airport. Or sometimes even cheaper – especially if your flight is one of latest and taxi drivers don’t want go empty back from airport, as shortly won’t be any passengers left.