child car seat hire

For anyone that lives in Florida/Orlando….?

I was wondering in Orlando, Florida can a child ride on an adults lap with a seat belt secured around them both in a vehicle?
I live in UK and you are allowed a child over a certain height to sit on your lap with seat belt around you both if you don’t have a childs seat. The reason I ask is because I am going to Florida in October and we are hiring vehicles, they are trying to charge over £150 for one childs seat and we have two children coming! So it would be cheaper to buy one over there instead but we will need to drive the car to the shop first to pick up the car seat so that would mean the two children riding on adults laps for the short journey to the shop and don’t want to get pulled over for this so need to check first.
Other than this, is there any shops in Orlando Int airport that we could go buy car seats before we leave? I know its a long shot but we gotta try!!!
Come on guys there must be some better ideas than that out there!!!

How old are the children, as after a certain age/height they do not need to be in a carseat, especially if they are in the backseat of the car. Why are you having someone drive you around or do you mean “renting a car” instead of hiring vehicles?

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