There are many reasons why someone would ask that question. An obvious one is in the question itself: I’m happy where I am and what I’m doing. I just want some extra, supplemental income. Check out: Ways to Make Money with a Real Estate License (Without Selling a Home).
Others might have other things going on that are taking time, such as wanting to finish college or they have current family obligations. They are just interested in a little extra money until their time opens up a bit. Perhaps others want to ease into real estate, while keeping their current job for a while. Whatever the reason someone would ask “Can a real estate agent work for just extra income?”, the answer is “YES!”
One of the biggest advantages of real estate is flexibility. It has schedule flexibility. It is flexible in ways to make money. It is flexible in the part time/full time department as well. Don't miss: Why Do People Choose a Real Estate Career?
Since you can choose when you work, Real estate offers a position that that can start with just providing extra income as a side hustle. In addition, you can choose from many career paths. This means you can fit your real estate career around your life.
With a real estate license, you have the power and flexibility to start part-time and increase your hours when it makes sense for your lifestyle. You might enjoy: How to Choose the Best Brokerage.