nice--buyPortable Folding Hand Truck Dolly Utility Cart Foldable Trolley Put in Backpack Push Luggage Flatbed Cart

I need something to put my carry on backpack on and then put in overhead still attached. Would this work?

Would this be a good option for towing around a car seat and luggage through an airport?

(a) how is the durability of wheels, is it good for smooth surfaces or can take of pavements and roads, (b) can wheels be switched easily ?

How is this cart on stairs?