We visited Versailles during August last summer. I bought tickets before we left and was so glad I did when we arrived. We bypassed the hour long line-up for tickets and went directly into the 20 minute line-up for those who have tickets. Even so, arrive before 9am. Just so you know, when you get off the train, follow the signs to "the Chateau" to get to the Palace of Versailles. There are no signs directing you to "Versailles". That is the town's name. We lost some time figuring that out. We got a full day pass but without the Hamlet and Trinion. After you walk through Versailles itself, the inside of other buildings is anti-climatic. What we were not prepared for while we were doing our planning, is the affect that these incredible historic places have on a person. You can easily feel overloaded after a few hours. It takes all morning to walk through Versailles, then there are the maze of gardens with all the fountains, the Grand Canal, and the Hamlet. These are long walks from the Chateau itself. It took us 30 minutes to walk to the Hamlet which was quaint and picturesque. So, a lot of time is spent walking and exploring the property. It is huge! Because Versailles is 40 minutes out of Paris, the travel time needs to be factored into the day. You may want to spend most of the day in Versailles, not rushing but enjoying the experience, have an early supper in the town and then continue sightseeing in Paris. When you read the travel books they encourage you to see 10 things in a day. We found that just isn't possible without feeling stressed and overloaded. Better to see fewer things well and enjoy the experience. This isn't Disneyland. Paris is a feast for the eyes, not a fast food stand. My advice as you plan, would be to allow yourselves the time to savour and experience the trip. Happy travels!