Very doable. I'm from the Canadian prairies and I use my TT year round for work..we see temps around -20c to -30c during the winter. obviously it's a little more prepared for the long stay, full OSB/durafoam skirting with one space heater under neath so you can keep the wind/cold from cooling the under belly so I can still use the plumbing/sewer. Durafoam'd the windows then plastic sealed them to give a double window effect . Also insulated the one slide I have..not sure how effective it is but I had left over foam
Big heat loss I found inside is the roof vents/ducts .. Fill them in with the foam and seal it up with aluminum foil tape. Reason being you don't need to hear your roof or AC unite and you don't want moisture escaping and collecting up there.
As for heating I run 2 good space heaters and my electric fireplace if it's below -25c outside. I barely run the furnace, usually just to bring up the temp on a real cold night when I get home. If you constantly run ceramic heaters they will actually dry your air out, being the only guy there for 10-12hrs a day I find that it's too dry so I shower with the roof vent closed to bring my humidity level up so my nose doesn't dry out lol.
Honestly ppl worry too much about it, if you leave a window open and a roof vent cracked and run ceramic heaters you won't hurt it. Have a towel near the windows to wipe down cause that's where it will condensate. when you go to leave you should open the doors and let the humidity that is there out so that it doesn't condensate n freeze on your walls when you shut the power off
In my experience of your dealing with temps above -10 you'll have no probably warming it up in an hour with everything going..cover your roof vents and it won't take long.
Hope it goes well for you! Cheers