In terms of budgeting, it would certainly be helpful if you intended your trip a few months or perhaps a year ahead. This would mean that you would be able to receive much lower prices on tickets. And as soon as you get to Nepal, then you'd be able to save money by doing most of your shopping in Nepal, rather than going to Nepal and seeking to shop in towns like Kathmandu or Lumba and pay exorbitant prices for what you'd buy.