I wouldn't leave a house in the frozen north without someone very nearby checking on it frequently. I personally know of two homes wrecked when the heat went out and the pipes froze (one a close relative). I used to watch a neighbors home that was perfectly maintained and one below-zero night I took my usual walk around only to notice a small rug in the kitchen was soaked. It turned out a pipe below the sink had frozen and sprung a pinhole leak that was spraying a mist of water out. Would have eventually been a huge mess. Another time I was walking by a neighbors house in the dead of the winter and noticed their sprinkler system had turned on and was creating a sheet of ice on their property and the street. Since I didn't know them at all I had to call the police who contacted the public works department who turned off the water to the house. While watching my fathers home one winter one of his heating pipes in the living room radiator sprung a leak. Another time his furnace pump died in the middle of the winter. I don't think you can safely leave a home over the winter without careful supervision.
We turn down the thermostat to 53 deg and hope the heating system does't quit during the winter. Also shut off the main water supply. To keep an eye on things, I have motion dection camera's with 24/7 access. For temperature monitoring, I have an internet connected thermostat with full control and again 24/7 access. The thermostat will also email me when/if the temp drops below or above the settings I programmed.
Most Television 'cable' providers will suspend your account (for a nominal fee/month) for your travel time. Same with XM Satellite Radio in a vehicle you are not using, or at your home, while you travel. And also home phone service. USPS will hold your mail for 30 days, then deliver to a specificied address. You can also have your mail forwarded But make sure it's clear with USPS that it's temporary, or they will begin notifying mailers of your "new" address.
Know your neighbors! So that in exchange for returning the favor, ask one you know well & trust if they will help (even for $), if you have no family in town who can. Many would be happy to hold a spare key to your house, watch your house, switch lights on/off (we now use timers inside & out), water your plants, drip water in case of freezing weather (If you live in the South - Northerners may have to winterize). We have a cleaning lady who will do this for a small payment. We have a neighbor who will pick up & hold our mail & grab our packages and then text us with a picture of the envelope if she thinks it might be important (of so, she opens & texts or scans & emails a copy of contents). She will even take care of our animals (but we usually take with us).
You can sign up with USPS to get daily notifications showing what mail you have ea. day. And activate notifications with shipping companies so you know when pkgs. are delivered (for neighbor pick-up or to UPS store box rental, where your mail can also go.)
Contact local police dept. with your schedule. Our district will send police to drive by & walk around our home while we are gone.
If you are going to Florida, the first thing to do is to change your state of residence to Florida so you won't be paying Northern State taxes. You will still pay property taxes on your home in the North.
There are NO US citizens only citizens of member states. WE must elect ONE domicile as our primary residence, ie typically where we decide to vote, license vehicles, etc. IF you own TWO properties in different states check out the tax consequences before you elect. Some states have varying caps on changes in taxable value, ie lower of CPI or 2% to maybe 5% depending on the State. In that you can ONLY domicile ONE state, on the other you are considered a speculator and receive NO capped protection. Example if your northern home is a HOT market and your area homes appreciated 6% and you elected FL your domicile (2% Save our Homes cap) your tax bill for your Northern home could increase 6%.