when I starting sending out renewal notices at 120 days, the letter states that our form needs to be filled out, and I keep using that to get people in to sign them. in 5 years, have never had anyone give me notice any other way. you have to train them. if you want them to sign the form, make it the only option. if you are going to let them submit their own, then you will have to be inventive to get all the leaseholders to sign it together, and be prepared for the chase after if they don't all sign at the same time.