回复：回复：租客的医生证明日期如果是你买房以后的，租客和前房主就可以说是你的问题。

I don't know law. I just did Google search. I found following.

"...If the landlord doesn't take care of leaks and mold grows as a result, you may be able to hold the landlord responsible..."

http://www.nolo.com/legal-encyclopedia/mold-rentals-landlord-liability-responsibility-prevention-30230.html

Any comments from legal experts here?