Every now and then you can accept a deal that pays back in 8 years, but only if there's a kicker to it, like the total cost of your investment (after repair) is clearly underneath what the property will actually sell for.Being super picky and selective in real estate is the key to success.

Was it simply turned off at the stop valve underneath the sink?  

Can you pull a corner up to see what's underneath?

While there are a few preliminary inspections for underground work, sewers, etc, the pre board inspection is the 'big one' in terms of the amount of work to be reviewed all at once.Here is a list of what is inspected at the pre board phase: Electrical - all wiring in the house is exposed and can be examined easily by the inspectorPlumbing - drainage, venting, water lines and other elements are looked atGas - a pressure test is shown to the inspector to show the connections are not leakingFireplace - the install and mainly the venting of the fireplace is inspectedMechanical - the furnace, ductwork and return air installation is reviewedBuilding - the structure, engineered work, soil bearing report and sulphate test, radon gas penetrations, fire barrier and many other minor items can be reviewed hereThis multitude of inspections can be helpful to identify any of the countless mistakes or omissions the builder can encounter during the construction process.

The solution is often to retain the soil on your side and you have multiple options here.

One thing I always do is run a layer of roofing felt underneath the floating floor.

What is the soil like?  

I always write up the best offer and then make acceptance conditions include inspection pest and water testing sometimes Soil and Geo in some areas with expansive soils that might break slabs.

It is the roofing companies responsibility to protect the property underneath.

The mold is being taken care of .Side note: water issues have started and are continually being addressed: gutter work, regrading of soil around building, etc.