I would never trust/use Yelp due to their shady business practices. It is common knowledge they try to get companies to pay them to bury bad ratings and move up the good ones. Who knows if they don't also get paid to create bogus good reviews from those who have never used that company? The link shown above also contains a number of terrible reviews where people were overcharged or billed for extra fees unexpectedly.
I would stick with known car rental companies that many others on here talk about. Even though some of the no name rental car companies may have a good reputation in Europe, they often have terrible service in the US. LOTS of older threads about that.