If your budget is about $400: Get a new shower head, and then upgrade your bath linens and swap out the vanity light. Fresh linens (and a shower curtain, if using) and lighting will make the space feel cleaner, brighter and more stylish. To avoid installation issues, select vanity lights that mount to the wall in the same way as the old lights.
Keep it simple. Although the wallpaper isn’t minimal, the pretty window film (used only on the bottom panes to maximize light) definitely leans toward the barely there category. It’s a marriage made in heaven. The unobtrusive window treatment lets the botanical wallpaper shine, while the wallpaper frames the window beautifully, allowing it to be a standout feature too.
If you are selecting a toilet, get the manufacturer’s specifications from the website or from a plumbing supplier before making a decision about what type will fit and operate properly in your home. Other options can be different seat heights, electronic controls and different levels of water consumption, to name just a few.
You probably won’t be able to move any plumbing around, but you could replace fixtures and other materials with stock, off-the-shelf products like you’d find in a big-box store.