Make sure you give your tenant a move in checklist of every defect in the house that needs to be repaired 

Also a defective T&P valve could be releasing water vapor if the unit is running hot.I would not be too concerned about a few spots of mold on a pair of shoes...they could have been put away wet, and with the ambient high humidity and dark location could easily have developed a little mold.Have you closely inspected the downstairs unit(s) for potential leaks?

Our thoughts now are knowing this we would only put in offer below list price knowing this defect?

You have to disclose defects or problems. 

All a WD does is create the possibility of the Grantee being able to sue the Grantor for a breach of the warranties if a defect comes to light post conveyance. 

Defective Enforceability.

I'm not positive about FL, but in IN you have to give the seller the opportunity to either offer to adjust the price or make suitable repairs (this could (should likely)  cause a subsequent inspection post repair period)Again, verify for FL, but under IN law (when you go to read your full inspection keep in mind)  Under Indiana law, "Defect" means a condition that would have a significant adverse effect on the value of the Property, that would significantly impair the health or safety of future occupants of the property, or that if not repaired, removed, or replaced would significantly shorten or adversely affect the expected normal life of the premises.So to ask for a purchase price reduction it would need to meet that qualification most likely. 

3.Binding Arbitration Agreement;...The sole and exclusive remedy of the purchaser(s) and the obligation of the dealer for the matters set      forth herein whether on warranty, contract, negligence or strict liability, is the repair of the defect.

We are tinkering with free market dynamics storing latent defects within it that are not fully understood by the many.  

When a seller wants to transfer a property through means of a limited warranty deed, he/she is not responsible to the buyer for defects that were in existence prior to original ownership.