I've never had a problem doing the following, nor have any of my friends who do the same.
Assuming you are planning on continuing to use your trailer, and as long as it is consistently above freezing during the day, you are generally good to go. If that concerns you then, as a three minute precautionary measure, pop the safety valve on the water heater and open all faucets and your low point drains. Don't forget to drain the fresh water tank and run the pump to make sure there is no water in the pump.
When the temps are going to be below freezing for more than 24 to 36 hours and you are no longer planning on using the trailer, do the antifreeze thing.
I would suggest that in the Richmond area you might generally want to winterize around late October.
Happy Camping! ///// Richard D.
2006 4x4 Ford 250 SD / 2007 Flagstaff 827 FLS
One very patient wife and one furry child who travels with us. Forty-two years of trailering and camping, and I still have a blast.