salamari_4010,
You give no indication of where you are from but I'll make the assumption that you are from the USA. That being said, there are some things you should take into consideration when planning a trip to Italy in the summer,
While Venice is located at about 45 degree north latitude (further north than Bangor Maine), the climate is more like Florida in the summer. Hot and humid... You're also dealing with buildings that often date back to the 15th, 16th and 17th centuries (sometime even older). On top of all that, electricity has become a lot more expensive than in the USA and air conditioning is not necessarily the "norm." Insect screens on windows are also not universal in European...
So, in addition to the incessant crowds (there were SIX cruise ships docked in Venice the last time I was there), is can be uncomfortably hot and humid in the summer. However, comfortable is a personal thing. If you are coming from an equally hot and humid climate, you may not even notice. If, however, you are coming from a cooler-dryer climate, it may be unbearable. Only you can make that call.
On the plus side, Venice, regardless of the time of year, has two personalities - daytime and nighttime. Many of the tourists are day-trippers (cruise ship passengers, coach tours, etc.) don't arrive until mid-morning and leave by late afternoon or early evening. So, the evening and nighttime personality is much different.
If you do decide to go to Venice, I would get an apartment away from the train station, bus station, and San Marco. Plan to put up with the crowds but savor the evening and early morning times. Venice is special and there's no place like it anywhere else. Flying into Marco Polo Airport and taking a water bus (alilaguna) to the Grand Canal or stepping out of the train station is like being transported back in time.
Good luck and have fun!