Use Uber or rent a car in Houston?

Hi! My friend and I are booking a trip to Houston early November. Our air bnb is located near downtown but we wanted to travel to places like the Kemah Boardwalk and the space center, amongst other places around the ocean. Of course we are going to spend time downtown as well. I was looking for pricing of renting a car and they seem okay but the surcharge for under 25 is what makes it more expensive, almost doubling in price. However I know uber can add up, especially if we go to multiple places in one day. Just wanted to know if anyone had advice or recommendations!