Here is a way to train your dog to relieve themselves if necessary indoors. My 14 yr. old Chihuahua named Pickles learned right away. He would use it when he could not walk far anymore. It shows senior dogs can learn new things! :) Simply get a large cookie pan that has a high enough edge to hold urine, etc. This one is 21 inches x 15 inches.
Simply place a newspaper on top. The newspaper advertisement dimensions seem to fit the pan perfectly (no glossy paper). If needed for training, first absorb some of their urine from a another spot. Place it on the newspaper in the pan to encourage them. Preferably place the pan against a wall and in a well ventilated area. Try to keep it clean and freshen as often as possible. Libraries discard newspapers if you need free ones. When disposing of newspaper in a bag be sure it does not have holes! ;)