A complete estate plan is a small set of documents, each with its own job. A last will names who inherits, names an executor, and names a guardian for minor children, and it takes effect only after death and through probate. A revocable living trust holds property during life and passes it at death without a court process; a pour-over will sits beside it to catch anything left outside the trust. A financial power of attorney and a healthcare power of attorney name who acts if you cannot, and they end at death. A transfer on death deed, in the states that allow one, passes a home to a named beneficiary outside probate.
Each document is signed under the law of the state where it is executed, and the witness, notary, and self-proving rules differ from state to state. The builders on this page carry those rules for the state you choose. The Signing Requirements Checker lists them for every document and state, and the Trust or Will tool compares the two ways of passing property on the numbers.