actually fresh tank location in neWr units depends on length.
some of the tiny streams produced in the last 10 years have front tanks...
this isn't the case 4 the op target, but is true for some single axle or tiny units.
the op needs to explore the owners manuals that are online,
and crawl under a few units and get familiar with this stuff....
the drain locations can be followed UP stream to the tanks.
there are 100s of threads here with pix of interior repairs and sofa extractions...
what is under many of the front sofas in the last decade is the converter/charger/12v feu'z and wiring bits.
the classics often have 2 battery boxes under d'sofa as well.
this stuff is easier to deal with than water boxes, but needs to be considered.
all of the true things that i am about to tell you are shameless lies. l.b.j.
we are here on earth to fart around. don't let anybody tell you any different. k.v.