If I have a personal account in my mothers name, and she adds me to the account as an authorized signer, if she dies, can I continue to conduct business and write checks out of her account? It was my understanding that if she dies, I can no longer conduct business for her because I have no rights of survivorship. The money in the account would go to her estate. Can anyone help me out on this one?

As an authorized signer, you should only have access to the account while your mother is alive. At the time of death, all rights of the authorized signer cease.

The money in her account falls to her estate. The personal representative of the estate then has the responsibility/power to establish a probate account and pay bills and expenses with that account.

To avoid this, you need to become an account owner. Some banks and state laws vary on how to actually accomplish this, so you may have to do some research on this one.

In Texas anyway, you can be added as a beneficary. In doing that the account does not fall in under her will and you would receive any funds.