Since we are in Texas we tend to use our trailer during the winter and not so much in the heat of the summer unless we head north for a few weeks.
I tend to sanitize once a year and that's late spring early summer. I also don't use antifreeze unless i feel we are going to get a very hard freeze, I do a good job of draining the trailer then blowing all the lines out. Now I do put some antifreeze in the bowl and traps.
Trailer lives on the side of my shop in the backyard so I get a beer or 3 and have at it.
2015 Ford F350 CC SRW LB 4X4
2016 Cedar Creek 36CKTS (My Last FR Product)
20,000 LB Reese GooseBox Hitch