I agree with NI's ideas. With electrical available, using a heat source other than your furnace, will be much easier than constantly refilling propane tanks. We have a 13' LQ, and one ceramic heater easily maintains a comfortable interior at temps in the mid 20's. A second one should help at colder times.

The water situation will be more difficult to address, and heat tapes are really your only alternative for exterior lines. I would favour the a/c tapes rather than the 12V variants. The tapes use a lot of amps, particularly on long runs, and I would be leery of how much your converter is able to supply on a constant basis.

Eliminating the wind from passing under the floor areas, will greatly enhance your comfort. Hay bales, fiberglass panels, plywood, something rigid to block the wind will help. If the trailer won't be moved, these could be installed a little more permanently.

You can purchase the dump totes with wheels, that have a larger capacity than your holding tanks. If one were left attached to your trailer and the dump valve was left open, it would fill the tote instead of the holding tanks. This would certainly work with the gray water, but the solids in the black water tank, would be difficult to flush into the tote. This could be a problem in freezing temps. An anti freeze should be added to the tank before it is used, which would prevent the tank and valves from freezing.

As was stated, a plastic liner could be added to your windows, along with heavy curtains to prevent some of the heat loss.

Over all, staying warm shouldn't be the issue. The water supply and waste will be the more difficult aspects to address. When I was first married, we owned a mobile home in upstate NY, a bad place in the winter. We had exactly the same issues you will face. Heat tapes, pipe insulation, power outages, frozen water lines, were all common issues that weren't fully resolved, until we bought our home.

I'm very sorry for your personal situation, and wish you the best of luck.

Are you sure that one is not the LP line running to the hot water heater? Is it black (or possibly rusted) steel pipe?

As far as the grey water goes, if you are going to keep it drained, it shouldn't be an issue. You can get tank heaters for those. They are basically a "blanket" of heat tapes that attaches to the bottom of your tanks.

Charlies is not out of buisness.  Called the number and it was answered.

http://charliesrv.channelbladelive.com/content.asp?nav=141213&cpid=29233&

You should come down and visit us this weekend..... http://www.showhorsemanagement.com/TarheelPlantationClassic.html

I have done a fair amount of cold weather camping with my LQ trailer and have learned a few things that might help you.   Unless you are going to park a propane truck next to your trailer you will need an electric heater.   While it is an investment of about $250.00...a EdenPURE heater (the smaller unit they offer is big enough for 300 sq. ft.) is the safest way to heat your trailer and you would not have to be afraid to leave it operating while you are gone. It also circulates the air from floor to ceiling and into the gooseneck much better than other types of heaters. If you need to use an extension cord to reach an outlet be sure to buy the shortest one necessary and heavy duty to prevent overheating the cord.  The ceramic heaters get hot on three sides and draw more amps of power.  A 2" piece of foam insulation board under your goose neck mattress will stop the transfer of cold to your mattress.  The water pump is vulnerable if it is screwed directly to the floor....it can freeze.  Put a square of insulation board under it.  The fresh water inlet hose where you put water into your trailer is another weak point.     A round piece of 2" styrofoam insulation will fit behind the little plastic door on your water inlet and keep the cold air from funneling down to your tank.  Leaving the cabinet doors open under your kitchen sink and bathroom vanity on cold nights is a huge help. If you have a cabinet door opening into the space where your fresh water tank is, then open that door also. Trailer floors are always cold...so a good pair of warm slippers and heavy throw rugs for the floors will make things more cozy.  You can pour RV anti freeze into your black water (sewer) holding tank to keep it from freezing solid and plan on draining your tank into a portable one during the warmest part of the day so it will flow.  I have repeatedly camped down to 15 degrees on unprotected camp sites and been OK.  Sorry to hear that it will be necessary for you to do all this.

I will fill as needed I have access to a frost free spigot...

Wow I didn't know that you could get a storage tank from those places I did have them come dump my camper years ago when I stayed in it temporaily...THx my tanks are the biggest worry with it... I will call and ask about one...

I would love to but all my extra will be spent on storage fees ,  etc for now. Rain check ?