Some of have kept o. briareus. Look under Journals and Photos for postings on Jetta, for instance. There are also photos of baby briareus.
Sometimes they are available through a local fish store, but as far as I know, they are not being bred for sale. Since you live in Florida, you might not find it too difficult to locate a briareus fo rsale.
I think you would need at least a 50 gallon tank.
You can find a lot of information on keeping an octopus in our Ceph Care articles (click on Ceph Care above) - have a look at the Equipment List and the Checklist for a start.
O. briareus is a very beautiful octopus and would be a nice one to keep.
There is a lot of unreliable information on the web.
I have seen an adult briareus kept in a home aquarium, and there is no way it would fit into a 15 gallon aquarium. You need plenty of room for it to swim, extend its arms, and also to take care of the amount of waste it will produce. The arms of this octopus can be two feet long, so it needs some room!
Also, I had a briareus hatchling grow up in my 19 gallon aquarium, and it was time to move her to a larger aquarium after 4 or 5 months (unfortunately, she died before the move). If you start with a smaller aquarium, you need to have a larger aquarium cycled and ready for the move - it takes too long to start one up as an afterthought.
So, at least a 50 gallon aquarium for a briareus, the bigger the better.
I would think you'd have a lot of trouble getting one egg, and it's not the best way to go if you could. The mortality rate is very high for octo hatchlings. You'd need to start with a few more eggs to have the chance of one living to maturity. Maybe you could find someone whose briareus has laid eggs and get some of the hatchlings.
If you have a well prepared tank loaded with amphipods and other very small creatures, your hatchlings would have a chance.