Hi Justin.
I work with Nautiluses in NY. We keep between 6 and 12 in a 280 gallon tank. They are hard to keep, but not impossible. They do need to stay cool - we keep ours at 17 degrees C. In my experience they can last in warmer water (23 maximum), but not for long. we have a recirculating system and our max lifespan is about a year. I think they do a lot better in open systems.
I wouldn't recommend them for a home aquarium for a couple of reasons - 1. they are not terribly active, so are not that entertaining. 2. they drop dead without any warning. 3. by the time they get to the commercial vendors they are often so moribund that your investment goes south within days. 4. they smell appalling once this happens!
Personally I think their behaviour is kind of cool, but I will admit that they're normally dead boring to look at. They are mostly active at night, so they're not a whole lot of fun in a lit aquarium. I have heard reports that animals kept in bright lights all day go blind frequently.
They're also kind of dopey and will find a way to get stuck in outlet pipes or otherwise bash themselves up on very innocuous-looking things. We have a UV scrubber running 24 hours a day on our tank and we still treat any minor scrapes aggressively, because infections seem to be a problem with captive animals.
On the plus side: They will eat from your hand (very cool!), and are not as shy as octopuses. They don't ink, they're not toxic and you could probably house them with other fish and inverts relatively easily.
Are you going to buy the one in the store? $65 is a pretty good price, generally speaking.