The amount of assets you have do not make a difference: you still need an estate plan.
Very few people in the U.S. are wealthy, but they still need an estate plan, according to the Napa Valley Register in "New dad wonders about estate planning."
One thing people with limited assets should understand, is that they might not need a trust to avoid probate.
Most states have a law that provides for the simple transfer of assets, if the estate is below a certain total amount. In such instances, even a will does not have to be entered into probate.
The amount varies from state to state, so you will want to check with an estate planning attorney in your state.
Nevertheless, just because you might not need to worry about probate, does not mean you should not get an estate plan.
If you have minor children, for example, then you will definitely want a will so you can choose who would be your child's guardian, if anything happens to you.
An estate planning attorney can guide you in creating an estate plan that fits your unique situation, including taking the size of your assets into consideration.
Reference: Napa Valley Register (August 24, 2017) "New dad wonders about estate planning."