anyone know a good place to rent equipment in kathmandu ??

maybe it would help if you specify what "equipment" you want? Trucks? Aeroplanes? Kayaks? Boots?

sorry
i need to rent all clothing needed for trekking above 5000m
jackets, pants, glasses etc

I think most places in Kathmandu rent good stuff, BUT watch this : jacket and pants and fleeces are even cheaper when you buy them. It is also a nice gift to yourself or a Nepali when you go back home. The quality of the material is Korean, which is less quality then the TNF or Marmot stuff, but for a 3 week trek there is no difference.
Should you not find it, there is also a new real TNF store, so that will always help.
Glasses : if you still can , better buy at home, seems they are quite expensive.
Have a nice trip,
Peter