How can I remedy this situation so I can purchase the property?

Most of the risks from lead paint isn't the liability from it being unsafe after it's finished, but from improper methods of doing the actual remediation.

Any problems will be discovered in the buyer's inspection period and can then be remedied through repair or negotiation.There's a lot more to all of this, of course.

After receiving the call from HOA, I called the tenant and explained to him about HOA and how to remedy the situation.  

Hi BP,I'm looking at a HUD property with BURIED OIL TANK and may also need MOLD Remediation in the garage and another room.My bigger concern is potential Oil tank leaks and soil remediation that can run thousands of $s.

Finally, SB 1994 gives a homeowner several remedies if a wrap lender violates the law, including the remedies in the Texas Deceptive Trade Practices Act.From the Texas Senate:"Senate Research CenterS.B. 199485R6359 CLG-FBy: Zaffirini et al.Business & Commerce4/11/2017As FiledAUTHOR'S / SPONSOR'S STATEMENT OF INTENTRecent years have seen a spike in the prevalence of a particularly insidious category of mortgage fraud involving so-called "wrap" financing, in which a seller finances the sale of a residential property that already is subject to an outstanding lien, often without notifying the buyer of the senior lien, or the existing lienholder of the sale.

Also, the correct term is lien (as encumbrance)  not "lean" as in rest upon or thin, gaunt or sinewy.My guess is that you're drawn to this property because it is there in front of you and you're frustrated because no one else has taken substantive active to remedy the long list of problems. 

If the company finds something, at least you'll have a path to remediation.

For example, if you were suing on mold that you discovered in the property, you should get a real estate attorney and have him or her prepare an affidavit that a mold remediation expert can put forward about the damages the mold caused in the property and why the previous owner knew, should have known or was deliberately unaware of the mold to your detriment.My state also allows attorneys fees on improper disclosure, meaning you can go really hard on these sorts of actions if you're going to recover, because the attorney can get paid $10,000 of attorneys' fees even if your recovery is only $4,000, for example. 

There might have been a column at downstairs unit which was removed at some point, we couldn't tell.So, my question is what would I need to do to remedy this situation ?