Private transport options

Hi everyone! A friend from Russia is visiting me in Bihar (Bhagalpur) and wants to explore Gaya and Rajgir. The problem is that this person has compromised immunity and does not want to travel in crowded buses or trains. In this case what's the best option for traveling around? I have never really traveled inside the state and neither my family, so I've got nil idea. Also, if you know good hotels and restaurants in both cities (Gaya and Rajgir) please recommend as well! Thanks in advance :)