Trekkers shopping guide to Nepal

You will want to shop in KTM - there are bargains to be made on outdoor equipment. The Thamel area is crowded with outdoor shops selling locally made copies of known brands. There are also a few shops selling the real thing at higher prices, but still lower than western prices. There are also lot of good second hand stuff, and lots of outdated second hand stuff.

You usually get what you pay for. If it is dirt cheap - it is not going to last. You could arrive empty handed to KTM an buy all you trekk equipment here, some of it will only last the weeks on the trail, other things will be worth taking back home. Your own well worn boots and a backpack of good quality are things I would bring and have well tested before coming here. If doing some more advanced independant climbing I might consider brininging my own small high tech tent and a latest state of the art gasburner.

Zippers and threading are the type of things that might not last.

Prices go up in high season.

It is you duty to bargain. If you pay the asked price - inflation will hit the country.
A good days sallary for a skilled worker in Nepal could be 400-500 rupies (2008).
A meal for a local about 50-100 rupies. Have this in mind.

Usually, if you know the game, you can end up with 50% of the asking price.
Be polite, look for a win-win situation.
Know the prices.
Donīt bluff, be prepared to walk out.
Look, think, come back.

Any agency will claim to be able to offer any service you can think of, it is up to you to find out if they know what they are talking about, if they have organized that kind of trip or gear before. 

Out of season:
More than 25.000 people crowd this place in the two peak seasons. There is a caravan of trekkers heading for EBC in October and April.
In early march finding lodges, a solitaire meeting with nature and bargains in KTM are easier. The downside is that it will be colder (downjacket temperature).