To obtain the tourist visa in Nepal is not difficult most of the tourist from different can get on arrival visa except 11 countries. But to obtain the non tourist visa in Nepal is not easy. Just like Business, work, study, research, marriage (non) tourist visas are quite difficult. Tourist walk the door to door of different government office for further processing. It is really quite difficult. Basically to enter the Singadurbar is quite difficult. For the Marriage, business, work permit they must go to Ministry of Home Affairs, "Boarder and Limitation Section" I have put some information in the website http://landscapetravels.com/ the interested people can be benefitted from this information. We also served them in non tourist visa obtaining and extension. But government made one good thing. Any tourist visa holder can switch to other category.
But many of the foreigners that I meet before during my work think Nepal is free country and everything is free. I found during my work, they want to live free and eat free in Nepal which is impossible.