A Will is less expansive to draft than a trust and may be appropriate in some situations; however, those situations are very limited. For example, with a Will, your estate plan will have court supervision through the probate process. If you have concerns that your estate plan will not be properly administered by a trustee, a court supervised process will oversea the plan and insure that your personal representative complies with your directives.
If the value of your California estate is under $150,000, your estate may be administered without probate and a Will may provide sufficient guidance to carry out your wishes. However, if the value of your estate is greater than $150,000 and your estate has to be probated, the probate fees paid to your administrator and to the attorney are significant. For an estate with a value $400,000, the attorney and the administrator will each be paid $11,000, plus there is the additional costs paid to the court for filing the petition, and the cost of publishing a notice in the newspaper.
Finally, a Will does not allow someone to manage your assets for you in the event you are incapacitated. Without proper instructions and clear language allowing your agent access to your assets, your family may have to petition the court for a conservatorship - clearly a situation no family wants to confront.
Having a Will in place is always better than doing nothing, for at least it establishes some guidance that ideally includes how you want your assets distributed and names the person you selected to probate your will.