Hi Tina,
There are arguments on both sides regarding rust-proofing.
My 94 has only a few spots of surface rust in the seams where the the rear door openings meet the ground effects and can't be seen with the doors closed (really can't be seen with them open either, - very small.)
If you do decide to have your car sprayed, then I would recommend (Now don't laugh...Walmart!) Yup, Walmart has an excellent reputation down here in Belleville, and this is coming from guys who own classic cars; not that they drive them in winter, but usually have them rust-proofed before being stored for the winter.
As for hinge lubricants DO NOT use WD40. It is way too thin and will disolve long before the end of winter. It also washes away the factory stuff that should be used (Lithium grease, a.k.a. White grease or "Jigaloo" - available at Home Depot.) Another risk of using WD40 is that it can cause rust to migrate. Ie: If you spray a rusty spot the rust will travel in the drips of the WD40, and when the lubricant dissolves you have a rust deposit.
Another good idea I employ is to give all your door and window seals a thin wipe with Vaseline before freeze up. This will keep your doors opening and your windows going up & down over the winter.
Happy motoring,
Armie

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