limited door skirts trap rust ?
 

looked at a 99 the other day....limited....and the pass rear door was rusting at the bottom. Do the snap on skirts, trap mositure and thus rust ? Just trying to keep my eye out for another 4runner and did not know if this is a sneaky spot for rust to hide ?
I guess it could have been building from the inside of the door and out, it had a little rust on the rocker panel too.

I don't have any experience with rust starting under the cladding on the limiteds but, rust could be starting there. Where ever the salt water sits unwashed I figure it will start doing its thing.
I used to live near the ocean. Salt spray would build up outside the car. And when you go to wash it, it would make it past the window wiper seals and inside the door in between the seams, rotting it from the inside out.

Never read anyone complaining about rust in that location but I suppose it could occur anywhere.

I'll be the same vehicle has cr@p loads of rust underneath then.

The rear trailing arms and frame near where holes are can be the worst areas.

I hate to see a rust bucket when someone brings one to Texas from up north!

It probably started from a clogged water drain hole in the bottom of the door

I have noticed that the cladding on the front driver/passenger doors has abrasively worn through the paint and into the metal on my 4Runner. The spots that have worn through are fairly small, but are already rusting and will need to be taken care of at some point. I think the cause of this is aging clips that hold the cladding to the body have become loose (or have straight up broke) over time and have allowed the cladding to vibrate against the paint. I bought some of the same clips at Napa and the cladding sits much more snug and has no movement. Just something to watch out for.

Aside from those rust spots, no other rusting has started behind the cladding on mine and I live in Alberta (if that means anything).