TM storage and access questions

Hi, a few more questions about TMs....

Is there any access to the inside floor when they are closed down? If not, do you have to raise both sides to get to things inside? I'm used to a pop-up, and I can get into the floor area with the top down.

How much floor room is there to carry "stuff"? I'm thinking specifically of an older 2518 here.

To load them for a trip, I'm assuming you open it up, load it, then close it down and hit the road?

Is there any outside accessible storage on a 2518? I haven't found any of this model in my area, so I haven't seen on in person yet.

I'm trying to imagine what preparing for a trip would be like. Fridge access, where everything would go, etc.

Thanks in advance for the help!