Renewal of Agreement after giving notice

Hello, Our 11 months rental agreement ended on March 31, 2016 and we have given verbal notice to the landlord in the end of March that we would be leaving the house. However, as we would be staying in the house probably till end on May or leave it as soon as we find another house, our landlord says we will have to sign another agreement for 11 months as we would be still in the house till May and they would just write it down that we are leaving the house till May 31 and they will return our advance. My question is, I have given the notice, am I really supposed to sign another 11 months agreement , even if they write down that we would be leaving till May 31, 2016, am I supposed to sign it. Also, I have another concern, they are bringing other people to show home while we are still in it. Is it legal and permissible for the owner to show home to other people while we are still in it and would be for another 2 months? Wouldn't be invading our privacy and a security concern for us. Kindly, advice at the earliest. It would be highly appreciated. Thanks