Trying to buy a multi family with existing mold

[Neil Timmons]

Greetings,

I am a new investor in Maryland with a building under contract.   Upon completion of the inspection we found that the vacant unit in the basement has a whole ton of mold from an ongoing plumbing leak from somewhere above.  There was mold discovered in the unit above from the water damage and the whole basement unit was squishy and wet.  The unit need its own rehab before all of the damage, but it is much worse then it was upon consideration a month ago.  

I am trying to see if anybody has had any experience dealing with a whole bunch of mold and how big of a deal it is or is not.  The seller has said he will O-zone the room, then paint over the boards to "get rid" of the mold and fix the broken pipe. 

I am asking for anybody who has been in a similar situation for advice.  Should I continue down this path and just make sure the owner turns the O-zone up to 11? Or should I work on getting the contract voided? 

The picture is the wall with the wet drywall had fallen down, the plumber ended up knocking all of the drywall down.  

N!