I would raise the issue as a title defect preventing settlement and demand that the seller resolve it.

Had a list of obvious defects/problems and we both agreed, signed and made copies.

Hire a plumber to fix the issue.I work to fix the issues whether property defects or tenants as I realize being in RE is better than a 9-5 job making someone else wealthy.

They still need to reveal any material defects known to them, but otherwise are very limited on what they can say or do.As a typical Buyer (which is likely your status with "inactive" license, but check your local RE licensing laws) if you are comfortable with the overall sales process, you can certainly use the listing agent (usually they are able to help you complete a standard purchase offer) and you can also negotiate the "cooperative" side of the commission.

@Mike Schorah Absent the contract giving the seller a certain time to cure title defects, the buyer can either wait or agree to cancel.

If you have an owners policy and the title defect is not listed as a special exception in the policy or a matter that is excluded from coverage, make the claim and allow the insurer to remedy the defect. 

My understanding is that regulations were passed increasing the time for condo owners and HOA’s to assert material defects in construction.

You could take the seller to court, but you'd probably have to prove that they knew about the issue and intentionally covered it up, and it would be an uphill battle IMO because un-level floors are a patent defect (easily found problem) as opposed to a latent defect (one that can't be seen easily just by walking around or inspecting the property).

Generally, a house stays put.I've been contacted by escrow long after recording, 6 months, to correct some "defect" in the filing.

Does the county do a title check and guarantee that the title is free of "defects"?