Gasoline fuel stabilizers are good for one winter season, long term gasoline storage is not a real good option. You can stabilize Diesel fuel for a longer period and diesel generators last much longer although they are more expensive.
If you do get a generator and want to use it for more than a few days get one that runs at the lowest possible RPM, preferably 1800 or less. These low RPM diesel engines can run for years with little more than oil and filter changes.
One of the problems with diesel fuel is algae growth but a good filter will keep it from contaminating your system. Diesel also provides more power per gallon. If you are half way handy with tools get an engine from India, it will require a lot of clean up work but will be inexpensive. The Chinese make some good inexpensive generators. Figure about double the horsepower to wattage. 30 hp for 15KW for instance.
I know it will sound crazy to most people but I personally recommend getting a battery backup for whatever kind of electric backup you have. If you don’t intend to have air conditioning you don’t need a lot. You could likely recondition a used fork lift truck battery that would give you at least a couple days storage and then charge it with only 3 or 4 hours with your generator. I’m not talking about a little 5KW generator but at least 15KW and a good 100 amp charger. Know that even a really good choice is going to use 1/2 to 1 gallon of fuel per hour. You want to make sure you are always at full load to get best economy. This is where the battery can be a big help. Two or three gallons every couple of days should be doable.
The feeling of security this will provide you is worth the cost. If you ever have a storm or the economy crashes you will be glad you did, so will all of your family that comes to live with you.
Actually my plans are to go with both solar & wind here on our homestead. I’m already scouting out deep cycle marine batteries to salvage