Our insurance obliges us to lift out once a year but, going from memory and without digging out the papers, the policy does not specify when to lift out or for how long. We generally lift out late in the year and go back in the water in the Spring, usually mid to late March.
We are on a swinging mooring, so obviously no shore power. If we left our last boat unheated and without a dehumidifier in the winter, we found that, even with some ventilation, black mould would develop on some of the interior surfaces. I guess if she'd been sailed regularly there may have been less of a problem, but with wet and windy winters where temperatures are often within the 0-5 degree range, these are ideal for mould and the chances are the boat will remain unused.
I recall, with much fondness, winter cruises in the early 2000s where we had sunny days but with frost or ice on the deck. However, recent winters have been mostly mild, but wet and windy.
Perhaps awol has the answer - sail, anchor or moor for "the season" and then rent a cheap pontoon berth with shore power for much of the winter prior to a brief lift out.
There is a marina near us on the East Coast (Fambridge) that offers exactly such a deal - summer on a mooring (which may include a "valet service" to bring the boat to a pontoon on 2 hours notice), and winter on a pontoon. I don't know how common a deal that is, but it certainly exists.
I figure that I'll be lucky to be able to sail for another 20 years and the boat will survive that long irrespective of how long it is out of the water each year. It's an expensive thing to own - and the price is pretty independent of how much you use it - so I want it in the water as close to full time as I can achieve.
For three weeks during August. Costs nowt as the marina wants my berth so give free lifts and storage , I avoid the masses who only seem to sail that month and work on the boat is much more pleasant in the sunshine.
, plus climbing a ladder with a spaniel over my shoulder wasn't too easy.
A spaniel! pah! Try a 35kg labradoodle��