She points out in the dream to how one handles with his personal abilities. The workshop is the site of the creativity, – from her points the dreaming of the world what he has dealt with. There he uses and checks his propelling reserves and motivation reserves and all his abilities. A repair workshop for cars can refer, e.g., to the need for personal attention and maybe after physical allowance.
Spiritually:
The dreaming owns spiritual tools which he can pull up at certain moments for his support. A garage reminds the dreaming of the fact that he has this special aid on camp and can use them any time.