Custom Carpentry: Staircase Slats / Storage Door

I am looking for a skilled carpenter or handyman to update my staircase and storage area. I have provided a "current" photo and a "mockup" photo for reference. Balusters/Slats: Install vertical slats along the open side of the stairs. I'm not sure if we should go with a hand rail or just the vertical slats. Ideally, this could be unscrewed in the rare case we need to move a mattress in or our. Under-Stair Door: Create and install a solid white door for the triangular storage nook underneath the stairs. Finish: All work should be sanded and finished in a clean, solid white to match the existing trim. Thank you!