It is not good idea that going to hire a guide/porter for the trek in Nepal Himalaya with out any registered company. If you are looking cheapest decent then you will find even US $ 10 per day. It is depend on season... But what are you looking for cheap? is there any safety for the sherpa/guide/porter??? Insurance, do you bring from??? Nepal is developing country and it;s going on even slowly slowly. If such educated like you, do not understand the situation and careless then who does do it??? Porter?? I think it is not allowed to write the price for guide/porter as decent... leave me private message.
please, visit the site
http://www.tripadvisor.com/ShowTopic-g293889-i9243-k4924672-Nepalis_treat_tourists_as_dummy_rich_people-Nepal.html almost 7 years ago