In order to purchase Nest items, you'll need to visit Nestco, which is inside the Shopping Mall.
At Nestco you'll find lots of different items that can be purchased with either Mulch or Dosh.
Some items have a level requirement – this means you’ll need to reach or be above a particular level to purchase those items. You can check your current level in the top-right corner of the game screen.
The level requirement for each item will be clearly displayed in each shop. Additionally, some items will only be available to Bin Tycoon members.