Nepal is a developing country, Outside of major cities area electricity on trekking can be scares. You should have to pay 100-800 NRs per hour to charge goods on many lodges and also many tea-house treks, including in Annapurna base camp trek, Everest Base camp trek and many others treks also. Chargers often won't work on low power solar systems you find right up in the mountains so u can buy alternative bayonet light to electricity power plug converter, which will only works in low voltage is highlow. The standard Nepalese electrical outlet is a three-pronged triangle so bring three-pronged triangle charger

Nepal is a landlocked country which lies in Hindu Kush Himalayan region. Nepal has monsoonal climate having four main seasons: spring, summer, monsoon, autumn and winter.

Below is a general guide to conditions at different seasons:
January to March (winter): In this season temperature will decrease at often 0°C (32°F) at night, with extreme cold at high elevations. It is possible to trek in places like the Everest region during the winter but due to extreme cold weather and heavy snow fall it may be quite difficult than as usual.
April to June (summer): In these months it is quite warm and dry weather. There is an abundance of blooming flowers in the Himalayas at this time, with rhododendrons, in particular, adding a splash of color to the landscape. This season is the best time to undertake mountain expeditions.
June to September (Monsoon): There will be heavy monsoonal rainfall in this season. Rains are generally lighter in high Himalayan reasons. In this season the mountain ranges are not often visible due to the clouds.
October to December (autumn): These months are cool and clear which is due to the end of monsoon, there is little dust in the air so this is the best season to visit the hilly and mountainous region

Visa in Nepal can be acquired on arrival at Tribhuwan International Airport, Kathmandu and also at the border entry points in Kakadvitta, Birgunj, Bhairahawa, Nepalgunj, Gaddachowki border of Nepal - India and Kodari on Nepal-China border. Visa can also acquire at the nearest Nepal Embassy. For visa renewal purpose you can contact at Department of Immigration, Kalikasthan at Kathmandu. A valid passport and one passport -size photo with a light background is required. Visa can be obtained only through payment of cash in the following currency: Euro, Swiss Franc, Pound Sterling, US Dollar, Australian Dollar, Canadian Dollar, Hong Kong Dollar, Singapore Dollar and Japanese Yen. Credit card, Indian currency and Nepali currency are not accepted as payment of visa fee.

Visa Facility         Duration       Fee
Multiple entry       15 days          US$ 25 or equivalent convertible currency
Multiple entry       30 days          US$ 40 or equivalent convertible currency
Multiple entry       90 days          US$ 100 or equivalent convertible currency

In Nepal, “Namaste” or “Namaskar” is said to an older or high-status person with palms together, figure up. It is used to greet a person in place of goodbye or hello. There is no limitation how many times you say “Namaste” but, it is better if you say once per person, per day. If You want to say “Thank You” then you can say “Dhanyabaad /'ðɅnjɅbɑ:d/ (Dhan-ya-baad)”