It can be challenging to rely heavily on bus tours while on a major vacation. It is because you are tied to be at a certain place and a specific time and going in huge groups can somewhat be bothersome.
In this case, it is best to rent a car. You can move around anywhere at anytime without the hassles of group tours. Usually, car rental companies have special offers that will give you big discounts on selected vehicle types.
Whether you are traveling in small or big groups, it is the flexibility of being mobile that makes renting a car a better choice when on tour.