The 89123 is actually Silverado Ranch which borders Green Valley. Very desirable area as well.
There a lot of Henderson zip codes. Some of the most popular are 89014 and 89012. The 89012 is actually Green Valley proper.
I own several properties throughout Henderson, Nevada and Las Vegas Nevada I also manage quite a few.
I would love to help you in your search for a home. If I have one available that works for you than it be ideal. If not I can certainly locate one for you.
Feel free to call me at your leisure.