Need advice for car in poor weather: On a standard car (no fancy tech except for a reverse camera), how do you use the side mirrors to reverse safely when it is really dark outside AND heavy raining?

Recently moved to a new area and i am facing this scenario:

It is raining very heavily outside such that the side mirrors are wet and difficult to see. You cant really roll the window down to wipe without splashing the passengers and the car interiors.

On a normal day, street lights are already dim and hard to see. It is much worse when it rains. Plus, I use these UV films on my windows. I have to use them because it is scorchingly hot during the day.

So under those above conditions, it is very tricky to reverse down a basement. Due to the design, it is better to reverse down instead of going head first.

So what i usually do:

1) Use the reverse camera. I can adjust its brightness settings to show the back clearly.

2) Use the hazard lights. The flashes from these lights can bounce off of the nearby gate. So they can give some sort of "guideline" for me.

That is all i can do. I am literally blinded on the left and right in this scenario. Without any passengers, I can bite the bullet and roll down the windows. But even then, it is tough because of the heavy rain.

Are there any rain guard to put on the side mirrors, to stop the rain coming down? I have no idea if these exist or what they are called.

Appreciate any help