Winterizing: blow-out vs antifreeze for longer term storage?

I would first drain everything, then fill lines with antifreeze to make sure. I would then drain again, and blowout all lines. Leave antifreeze in P-traps, and enough in tanks to protect the tank drains and valves. I would not leave antifreeze in the lines, water heater or fresh water system for that long. Simpler might be OK, but for long-term, do everything you can.

I live in the same vicinity. After having AF turn to some kind of nasty gelatin type slime in my fresh water system 5 years ago, I started just blowing it out.
This has worked out great! Just remember to put some AF in the P-traps and dont forget to blow out the outside shower and tank flusher.

If you blow out the water there is nothing to freeze. Used both methods - blowing probably takes a bit longer but it allows you to get on the road quicker as you don't have to purge the pink stuff from the system. Just remember the small valves are the problem points with either method - you have to make sure that things like the toilet valve get properly purged/winterized.

I'd blow it out after I made certain the black & gray tanks are really empty. I'd also chlorine shock the entire system, flush, and then blow it dry. Things that grow in damp places scare me.

Drain, pump the pink, then blow the pink. Leave the pink in the p-traps, (or like me, remove the p-traps under the kitchen sink and bathroom sink, but not before getting some down the holding tanks.

Make sure holding tanks are empty as possible and clean as possible. Then the pink will help lubricate the slide valves.

By-pass the water heater completely, just drain it. Put the plug or anode rod back in, but don't make it tight-tight. Leave it so it will turn very, very easy. It will rust up after 3 years. If you make it tight, it will be almost impossible to break loose. So absolutely do not snug it up. And absolutely do not leave it out. The threads on your tank will rust up making it near impossible to put a new plug in (after 3 years). So (1) bypass, (2) drain completely, (3) flush it out with a tank flusher to get all the sediment out of the bottom (4) let that drain completely, (5) re-insert the anode rod or plug, finger tight (or a little less), keep it so it turns easily both directions.

I don't understand the logic of putting in the pink stuff only to blow it right back out. That does not make sense to me. I would do one or the other, but not both.

And if it were me, I would just blow out the lines (pushing a lot of air through), add pink stuff to the traps, and call it good.

I used to pump the pink stuff through, but went two winters (with temps well below 0 for a week at a time) with just blowing out and no issues.

You will need to remove the pink anyway.... why not sooner than later?
As long as you are not putting water in this would seem to be the best method.
Actually blow out the water first, pump anti-freeze, then blow out again.
Probably save the anti-freeze as it will not get much dilution.

This from a person that has never winterized :R

I'm in Minnesota (brrrrr). Been camping for 30 yrs or so and only use pink in traps. Been blowing out for yrs and never a leak. Each to your own, they both work.

6 bucks for pink...no brainer for peace of mind for me

Other things to consider when preparing for long term storage. remove the battery, and place the trailer on blocks with the tires off the ground, mouse proof it as best you can, leave the refer door open, wash any and all cloth items prior to storage, and remove all personal items.

We live in Oak Harbor, If it is near, we'd check on it once in a while if you like. ( no charge )