Senior fellow golfers, which is better to rent in Serbia, Golf or Skoda Octavia ?

It's basically whatever car you get, so don't worry about it. Also, most of the cars are manual because there are a lot of hills and traffic lights in the city.

Golf, diesel version is all, absolutely god car, no place can't go, too powerful

Car rental cannot specify models. The cars you said are compact models. The models on the website are just representative models of this level of car. The possibility of actually getting this model of car is very small. They will all give you cars of the same category.