Seasonal homes are fine (I own one with a mortgage on it upstate NY) but you need heat. I'd say it is worth it to put in something -- even electric baseboard that you will rarely use -- which would be cheap and not only enable you to refinance and take some cash out but will also help you tremendously when you sell it. Right now a buyer would have to purchase it as a primary residence and do a 203k rehab loan to put in heat etc.
Bank of America Home Loans
Putting in electric baseboard heat is a great start. There is a new kind that is oil filled and is more efficient. We have done this in properties that were unable to finance without heat. Also look into propane fueled Rinnai systems for smaller open area cabins. They work great. Many of these can be controlled from the internet by installing a control unit from Proliphix.
Peace, love and saving energy!
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