I definitely can't relate to wrenching outside in cold temps like that because I live in the California Bay Area. Maybe you have one of those places that rents garage space with a lift by the hour.
Changing all the fluids is really a very easy thing to do. The hardest thing I've found is the drain and fill plug on the front differential. They can be really welded on and prone to strip because Toyota decided for some stupid reason to make the plugs with an allen head.
Services like this at a dealership are a serious ripoff. 30,000 or 60,000 mile services are a good example. I don't think people realize what they are getting for the huge price tag they charge for these services. You're basically getting fluid changes, driveshaft greasing, brake inspections, checking tire pressure, a replacement of your air filter, maybe replacing the spark plugs and just looking around for other things they see while they have it on the lift like torn CV boots and oil leaks. They like using the term "Multipoint" inspection to make it sound like they're doing a whole shit ton for you but what I mentioned is really what they are doing for you.
For those finding this thread and are interested in saving themselves a ton of money, here's some videos covering fluid changes and basic maintenance for your 3rd Gen.
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<iframe width="560" height="315" src="https://www.youtube.com/embed/rnyK3V-OGn4" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>
<iframe width="560" height="315" src="https://www.youtube.com/embed/RumPXivBlk8" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>
<iframe width="560" height="315" src="https://www.youtube.com/embed/oQsxmi-CNng" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>
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