Universal doesn't require park reservations in order to visit. If you are interested in buying the Express Pass (their version of a skip the line service), those do have the chance of selling out the closer you get to the actual park day.
You can use Express Pass any time you want. There's a version that lets you use it once and there's an unlimited version, though that one is more expensive. Express Pass is good for every ride except for Velocicoaster and Hagrid's.
Just letting you know this, but I checked your dates and both Express pass types are $200+ per person per day since your dates are so close.
I would say most likely no. You're going during summer vacation when kids are out of school as well as 4th of July weekend. I would expect it to be VERY crowded in Orlando, not just at the theme parks (Disney, Universal, Seaworld).
I would say most likely no. You're going during summer vacation when kids are out of school as well as 4th of July weekend. I would expect it to be VERY crowded in Orlando, not just at the theme parks (Disney, Universal, Seaworld).
Second this, although you may see slightly lower crowds on the 3rd 4th at Animal Kingdom or Hollywood Studios, since many guests will be drawn to Magic Kingdom and Epcot for the big fireworks shows.
With Universal, the general rule is crowds are highest on weekends and federal holidays since universal has such a large proportion of its guests who are local annual passholders. So I would aim for Universal on weekdays other than the 4th.
According to Undercovertourist, on 6/30 the one time use Express is $231 per person and the unlimited is $261.
On 7/4 it actually dips a little bit with the one time use being $221 and the unlimited being $251. 7/3 has the same price as 7/4 but 7/2 is the same price as 6/30.