I had a plumber do a full hydro jetting clean up and he advised me that there may be a cracked on the sewer pipe a few feet away from the city drain pipe.

It's given me a pause if I think on it too much, but someone was the first with a jet too.

Aside from the floor structure in a modular home (larger joists) the homes are built essentially to the same standards depending on the manufacturer.Check the hydro cabinet door and find out the manufacturer.

If you feel the wholesaler or agents are so unfriendly, I wouldn't deal with them even though deal is great.I want to mention few investors who worked are good to do business, Chuck (American Home Buyers), Rene (Daniel Acquistions), (Rob)Jet Lending.

Buyer has accepted but contract not yet fully executed, as many know the way FNMA works is you make the offer, they give you a verbal acknowledgement, then you have 5 days to "formalize" your offer with their REO addendum, then they turn around and execute the contract.This home has some high end stainless steel kitchen appliances, Supra washer dryer combos (two of them), Dorn Bracht faucets, brand new air conditioning units for outside Gazebos, steam shower body jet roman tub modular units, Miele dishwasher, 48" long SS outside BBQ unit, etc etc etc...and because the home was never 100% finished, some of those appliances were not hooked up or installed, they sort of sat in their space but some still had styrofoam wraps around them or manuals taped over them.So, I listed all those in my contract to purchase, where you typically list included items, like ceiling fans, window treatment blah blah blah.The Listing Agent wiped all that out.

Im currently dealing with this now so this came from the plumber He is trying to fix a drain, not hot and cold supplies, there should be no supply connections to his drains.But the trenchless solution will only work between two points with no branch arms, if branches exist, they need to be hollowed out later and it's really tricky.Also, trenchless epoxy liner is not a good match for a tree root penetration issue, because for that to work optimumly you need to have the interior of the pipe rimmed round and jetted clean prior to applying the liner, or else the liner will assume the shape of whatever debris is inside the pipe, if it's a chunk of tree root, then your liner will take the shape of that tree root.

So they snaked it and jetted it without ever running the camera through?

Those Hydro/Water (Hydro = sewer?)

There are other flood zone types that do not have determined flood levels... for which you have to spend money with an engineering firm doing Hydro analysis to find out. 

To finish up-The buyer is having sewage back up from the pipe somewhere and the plumber that came out "jetted" the pipe and found several pieces of cast iron pipe that was breaking off.