Winterizing assumes your RV sits empty and unheated all winter. Ours does not, because we drive it somewhere warmer. Here is the full-timer version, including the one job we do not skip.
Wet bolts are the greaseable pivot bolts in your trailer suspension, and most owners have never touched them. Here's the full undercarriage routine we run on our fifth wheel, done the way Lippert and Dexter say to do it.