6*10 kitchen prewar:

-change oven location
-change fridge location
-change sink to a regular new sink
-take out old cabinet +countertop
-put new cabinet mid range
-put new countertop

Can this be possible on a low budget <30k?

and what can is allowed to do without asking the permission of the coop?

Switel,

It is doable if you do not need new appliances. For a kitchen renovation like the one you are talking about you do need permission. When on a tight budget we have been installing many ikea kitchens. Personally I like them very much, you will find some people who feel they are cheap. You will find many Ikea kitchens on website:

http://www.primerenovationsnyc.com/blog/