I have used different rental car service in Spain, Italy, UK, so I believe I can compare things already.
I wanted to give a fair review about what you can expect and what was our experience. After a while of research, what car to rent I decided to give a try to a local rental company.
Advantage
Shouldn't be any false charges after the trip
No huge deposits while taking a car
It was easy to communicate with BSG company
The price was fare 15EUR/day.

Some drawbacks:
The car that we rented was I guess around 10years old
The salon was a bit smelly and dirty
Window cleaners werent working normally, during the rain it wasnt cleaning properly
Cleaning was just a random water, which in the end was even dirty
Gearbox was not in the good shape also
Too little info on their website to get a normal impression about their vehicles

From facebook pictures I saw that they have some new car models, but they dont write any info about the car on their website. Overall price is a little lower, but I werent happy with our experiece.