Hey! Darjeeling and Gangtok,Sikkim approximately have the same budget. However,if you are plaaning for offbeat locations in Sikkim as there are quite a few, then it would be comparitively more expensive.Again, there are a lot of options ranging from cheaper hostels/homestays to luxury hotels.Its up to you to chose but by and large they are more or less of the same budget with Sikkim being a tad bit costlier.