Should I be concerned with putting a lot of Miles on my Prius

It will depreciate whether it's driven or not. It's 10 yrs old - so not really much finite residual value. If I were you, I'd be driving it. Companies don't rent cars if they're not making a profit - which you might as well get. I only ever rent if I've had to fly somewhere and need a car at the other end.

You've also paid your insurance on your PRIUS - if you rent, you've got to pay a 2nd lot of insurance on the rental car.

Plus - you've still got to put petrol in it - and, unless it's another PRIUS you rent, it'll use far more.

 

I wont worry to put kilometers/miles to car what i have. I wanna think thats what they are for and more cheapers cost/km will be if i drive more. I have a friend who buys new car about every second year, he is afraid to put kilometers to those. Cost/km gotta be huge for him.

I have logged all my(ok, maybe some windscreen fluids and washes may be missing) costs of my current car to Fuelio android app, also monthly loan paymen, as i wont get em back since car value drops.
Currently cost is 0,34€/km, umh sorry this time at saturday morning my brain is not ready to convert that usd/mile. Previous Toyota Avensis 2.0 wagon was 0,42€/km.

Edit: but yeah, i dont drive so much, maybe 22-25k km/year.
Edit2: Something extra to compare to those costs/km. In Finland you got 0,43€/km tax free is you have to use your own car at work. People who drive a lot(salesmans/service) can easily maintain new car on that 0,43€/km if they are allowed to drive own car.