hydration of new imports

[simpleyork]

So say you pick up a new import. Seems to be a lot of them tend to have lost weight around the hind quarters due to shipping/stress. So you get them home, how would be the best way to get them up and going . . . I've heard a luke warm shower with the drain not plugged works well, what are your thoughts?
may be per species it could differ some as what to do.
Mountain horned dragons, and sailfin dragons are on my mind, Ive just seen alot of those two species that are in fairly bad shape at shows which keeps me from buying them.