A day in Versailles, is going to leave you wanting...

A day in Versailles, is going to leave you wanting to see and do more. Need to spend couple of days to take in Versailles like Louis meant it to be experienced - without the luxary, of course.
Recommend doing the gardens in the morning, when it is cool and calm. Use the car (4wheel) rental to see the garden quickly, you will not be able to walk the whole thing unless you are a seasoned hiker.
Visit the palace in the afternoon, when it is scorching outside.
Unless you are visiting in Winter, in which case you should do the Palace fist and then the garden