If you are travelling across Rajasthan then a good day trip from Jaipur would be to Ajmer and Pushkar. With a distance of 150 Kilometres, it is a smooth ride on the well-paved highways that cut across the state. Check with your hotel travel desk for car rates or you can check with the many car rentals that you will find across Jaipur. It’s advisable to negotiate a fixed round trip rate so that you are well aware how much you will end up paying at the end of the trip.
I went to this day trip to Ajmer and Pushkar during my grand Rajasthan tour with my family. I had covered Jaipur -> Ajmer – Pushkar -> Jaisalmer -> Jodhpur during this trip. Considering my toddler daughter at that time it made sense to book a TATA Indigo rather than TATA Indica as the extra space would make sure a comfortable journey for all. If you are travelling during October to February then a non-air conditioned car will suffice but during rest of the season air conditioning is a must.