cookie style saving without cookies

I have a realty site where people want to be able to save properties but don't want to enter a username/password, etc. My first thought is just to save the info to a cookie but am not sure if this is the best way. If cookies aren't allowed, they will loose this functionality. I had thought about grabbing their ip and just writing it to the db but the ip isn't necessarily static. Is there a better way to do this? Thanks!