I do all of the above- and release my roof at the windshield, so it is relaxed over the winter. The car is covered with a fitted cover with the windows down a crack.

I hate to use the "W" word, but Walmart has large silica gel packs in the firearms section. They are sold for use in gun safes.

I top off with ethanol free fuel

Your decision should be driven by whether you believe driving 700 miles has introduced enough contaminants into the oil, e.g. acids etc., that it degrades the parts that sit in it for several months My guess is fresh oil is the safer choice, but its your car and your wallet.

BTW: if someone places such a high value on one's 986 to preserve it from winter elements by garaging it, why try to save a few bucks over low cost preventive items such as changing roughly 10 quarts of oil.

Actually, its not the value I place by garaging it as much as not driving a rear wheel car in snow weather;I have an Audi for that.

From what I hear, these cars apparently do reasonably well in the winter with the right rubber on them. Within obvious limits, of course---deeper snow is a no-go. But I just hate the crap they put on roads to melt snow/ice. Had a chance to see the underside of my winter DD (a Mazdaspeed) up on lift a few weeks back, when the clutch was being replaced. Gawd, it looks awful under there, rust everywhere! :eek: My Box is 6 years older and you'd be hard pressed to find a fleck of rust anywhere. I like doing what DIY I can on the Box, but if it looked like the Maz underneath I think I'd pass on that.

NE Ohio winters are destructive as hell on cars.

...and then there's that, the Magnesium Chloride used in Colorado reeks havoc to the entire undercarriage

i plan on starting the engine up once every 2 weeks and let it idle and warm up to operating tempurature so not changing the oil is fine in my opinion with just 700 miles on the oil.

Doing that is one of the worst things you can do to the engine. Unless you are going to run the car at highway speeds for 20-30 min., you are far better off to follow some others advise about fuel stabilizer, fresh oil, a good battery maintainer, and then just let it sit. We do this with several special customer cars every winter, never had a problem.

That may be what they use here as well...I've seen snow plow trucks spraying a liquid mixture onto the roads after a snow or freeze.