JB said:From someone who has a one-year old, if the high chair is not safe, you need to throw it away. Heck, you can buy a brand new high chair for less than $60. If your renters inquire about it, rent it to them for a few dollars less than the local companies who do this. After the third rental, you will start to make money.
EDIT: Yes, I would make them sign some kind of waiver. Just draw up a document you can email to them. They can sign it and mail it back to you.