Legal Question in Real Estate Law in California

It depends on what you want to happen to each of your shares if you die before the other. If you hold title as joint tenants, and you die, you can't leave your share to anyone else in a will. Your sister will automatically own 100%. If she dies first, her children would not get her share; you would automatically get her share and own 100%. The advantage, if that's how you want it to be, is that you don't have to have a will, or probate or anything. It's automatic. However, if she wants her share to go to her children, and/or you want to be able to give your half to someone else by will, you have to take title as tenants in common, and each prepare a will.