How do you adjust the doors?

My gf's XJ has all 4 doors sagging. Its a 99 Sport, and has does have a salvage title. I'm not sure on the extent of the damage when it became salvaged, but i've tried to look it over and haven't really seen anything that would lead me to believe its had serious damage to it. All 4 doors sag down enough to keep the factory seals from working, so when you drive down the highway, its like being in a wrangler because of the wind noise.

Is there a way to adjust the hinges that much, or any ideas on what the problem might be?

I think i found something in a thread that might help out. I read that i can try to loosen the hinge and push the upper part of the door in, but my concern is that the gap is pretty big, big enough for it to be a concern when it rains, because stuff starts getting wet inside all 4 doors.

Never looked at the rear doors but the fronts are shimmed.

The door strikers can also be adjusted. The hinge pins get worn. The hinge (on the door side) has some adjustment after it is loosened. The bolts are easy to funk up. I've used various materials to make extra shims, copper sheet or aluminum works well.
I rarley mess with the hinges or the pins. I adjust the striker and use a block of wood to bend the door a little top or bottom to get it straight. Roll the window down first.
Or if needed a 18" piece of 2X4 and a floor jack to bend the door/hinges up.
I close the door as far as possible, jack it up, positioning the jack near the handle end. I do it in steps so as not to over do it. Re adjust the striker and/or adjust the top/bottom cant if needed.
I close the door and use a dollar bill, to check the the door rubber has a good seal some contact/resistance all the way around when pulling the dollar bill through the seal.
I occasionally have my doors attacked by speeding trees and have gotten pretty good at getting them to seal again.
One of those procedures that requires time and patience and some help from a reliable buddy. Brain often works better than brawn.

Sounds like a project for the local community college auto shop. I've used them, they usually do OK, they get graded on there results.