Mike, we live in Arizona and we also get occasional freezing temps. We always winterize after each winter trip. We pay less than $3 a gallon for the pink stuff at Wal-Mart, and we need roughly two and a half gallons each time. Spending less than $10 each time gives us peace of mind and is much less expensive than frozen pipe repairs will be, not to mention the inconvenience factor too.
Enjoy your trip.