I think I bought ticket to nepal from Sunita Shrestha ( I think she runs her own Travell agencies back in Nepal too)  3 yrs ago. She gave me good price at that time. I didn't face any problem at all. I spent whole 4 months back in Nepal. One time I bought ticket from Rakesh Shrestha (He is an agent of Worldwide Travel and tours which you can see the pop up on the top of sajha). Just call them, they will give you their price and if you feel that is reasonable then you r home dude. I assume that  you are trying to send somebody.   


                                          There are lots of threads in sajha about Air fare. I think one of the sajha celeb called "magorkhe" wrote something like this " just tender quote".



Good Luck