Even if you are not the owner of the property, you are requied to disclose. Federal law Ignorance can be more expensive than education. It is advisable that you have your tenant sign an acknowledgment that you have complied with these requirements. State Disclosure Requirements Disclosure is the name of the game in real estate today. When in doubt about whether to disclose something to the tenant, do it, and do it in writing.
Some states have extensive disclosure requirements on leases and sales.
Many states now require Radon Gas disclosure. If the tenant does not exercise his option to buy, you keep his money and find a new one. They often sue you to try to get it back. This is why it is important to make sure your paperwork is in order and that everything is clearly spelled out. Ignorance can be more dangerous than education.