A soggy, 20 year old trailer is absolutely a tear down, even if it's in quite a bit better shape than this one IMHO. Those things have glued in panels that turn to roach sugar, I've never seen one over 15 years old, regardless of how clean the tenants/owners kept their living space, that didn't have a massive roach infestation hiding somewhere.
My good friends bought a house that had been shown on Hoarders and they had to empty out the prior owner’s belongings after they died. They said that this person just opened up some drawers and their cat had been using them as a shitbox for months without being emptied. A million other such gross details. I helped them out in day by going over there to wipe out their kitchen cabinets with bleach. By that time the stuff has mostly been emptied out. They said that there had been a refrigerator there, sitting unplugged and full of rotten food but the door was closed and the seal intact. So they tried to just get the whole damn fridge out to the curb and hauled away.
But! They got it to the doorway and it was one inch too wide so of course they had to open up the fridge and take its door off to make it narrower. No dead bodies inside but there might as well have been.
I have done hurricane disaster relief before, and I can attest that there is no smell on this planet that equates to a refrigerator unplugged for several weeks but still intact