Do you need multiple bunks?

Bunks expand the number of troops you can train in one go. Adding and upgrading bunks will make it easier to train troops which make you stronger, better at gathering and helps with completing daily challenges and events.

If your account is a farm then you may not need so many troops so the bunk may be less important to you, but otherwise you will want to have at least a reasonable amount of bunks and level upgrades.