Stander Security Pole and Curve Grab Bar, Elderly Tension Mounted Floor to Ceiling Transfer Pole, Bathroom Safety Assist and Stability Rail, Metallic Black

This is what we put in the shower for my mother, until we were able to get proper grab bars installed, and it worked well for her: https://a.co/d/0dm5Islz It's definitely not cheap, but it was sturdy (have to make sure to install properly) and caused no damage. After getting shower grab bars, we used it by the toilet. Mind you, it says NOT to put it in a shower. My mother was about 5'2", and I don't remember her weight, but at that point she was a healthy weight still, as she was still eating okay, I.e. not super skinny, but definitely not heavy by any means. I hope you're able to find something that works for you!