The woman who helped me at the desk in Rome's Termini station was very nice and helpful. She told me that if I returned my car before the prearranged date that I would be reimbursed for the unused time.
This apparently is NOT true and I was charged the full amount, but only used the car for half of the time.

Compared to other companies Rent4U is expensive, and the insurance policy options are confusing. The woman working at the desk advised me against a full coverage policy saying it is just too expensive and to just "be optimistic" that nothing would happen.

To return the car to the garage there is no one working for the company on site, so you have to send a text message via WhatsApp with photos. Which I did and no one ever responded or got my text. They had no idea I had even returned the car even though I had followed the instructions as they were indicated to me.
Totally unprofessional company that I will never use them again, especially since there are way better options and service out there.