A rental bathroom stops feeling temporary when the basics start to feel chosen instead of inherited. You usually do not need dramatic changes. You need the room to feel more coherent, better managed, and less like a placeholder you are enduring.
Improve the basics you touch every day
Towels, bath mats, shower storage, and better counter control do a lot of the emotional work in a rental bathroom. If those elements feel intentional, the whole room feels more lived-in.
Reduce the signs of improvisation
Visible cords, flimsy temporary storage, and too many mismatched stopgap fixes make a rental bathroom feel more temporary than it has to.
Make the room feel coherent, not decorated to death
A rental bathroom feels better when it is calmer and more consistent, not when every surface is trying to prove personality.
Bottom line
Rental bathrooms feel less temporary when the daily basics improve and the visible compromises shrink. Coherence matters more than dramatic transformation.