Litter box training is something that kind of depends on the rabbit. Most rabbits instinctively use one corner as the "potty corner." Some are really neat about it, and always poop and pee in that one spot. Others aren't so clean, while they may pee there, they may drop bunny poo anywhere they happen to be at the moment. Cecal pellets (night feces) can wind up anywhere, as well. Like most animals, rabbits use their urine and feces to mark their territory, so some elimination outside of the corner is inevitable. Litter box training is often as much a matter of the rabbit training you where it wants to go as the other way 'round! A lot of people wait until the rabbit picks a corner, then put the litter pan there.
I'm sorry if my fellow breeder's words of caution discouraged you. However, I am glad you are going to look into the subject a bit more before getting a rabbit. I enjoy breeding and showing rabbits, but it isn't for everyone. I'm much more comfortable selling a rabbit to someone who says, "We bought the cage, and the feed, and the hay, what else do we need?" before they even set foot on my place. Believe it or not, I have had prospective buyers that have said things like "Oh, I just figured I'd keep him in my bathtub until I get paid next week, and I can buy a cage then."
And no, they weren't kidding!
It's kind of odd, how rabbit shows work. In almost every other kind of animal I can think of, the show animal is groomed to within an inch of its life! How well you can groom can make or break your animal in the showring. It's almost the opposite with rabbits. A rabbit is shown in as natural condition as possible. The coat is to be clean, and free of mats, but any sign of trimming, plucking, coloring, or any other attempt to alter the natural appearance of the coat is grounds for disqualification. The condition of the rabbit's coat is supposed to result from the excellent health of the rabbit, not the skillful application of grooming products.
I keep playing with the idea of getting a couple of Flemish Giants myself. I work with 5 rabbit breeds, 4 of which run 4 pounds or less. My largest breed is the Harlequin, which tops out around 9 pounds. Inevitably, people see one of my Harlies and say, "that's a big rabbit!" I'd love to be able to point to an 18-pound Flemish and say, "No, those are just medium sized. Now, that, that's a big rabbit!" Every once in a while, I do get a call from someone who is looking to buy a really big rabbit as a pet, so who knows? I may add a 6th breed yet!
I'm sorry if my fellow breeder's words of caution discouraged you. However, I am glad you are going to look into the subject a bit more before getting a rabbit. I enjoy breeding and showing rabbits, but it isn't for everyone. I'm much more comfortable selling a rabbit to someone who says, "We bought the cage, and the feed, and the hay, what else do we need?" before they even set foot on my place. Believe it or not, I have had prospective buyers that have said things like "Oh, I just figured I'd keep him in my bathtub until I get paid next week, and I can buy a cage then."

It's kind of odd, how rabbit shows work. In almost every other kind of animal I can think of, the show animal is groomed to within an inch of its life! How well you can groom can make or break your animal in the showring. It's almost the opposite with rabbits. A rabbit is shown in as natural condition as possible. The coat is to be clean, and free of mats, but any sign of trimming, plucking, coloring, or any other attempt to alter the natural appearance of the coat is grounds for disqualification. The condition of the rabbit's coat is supposed to result from the excellent health of the rabbit, not the skillful application of grooming products.
I keep playing with the idea of getting a couple of Flemish Giants myself. I work with 5 rabbit breeds, 4 of which run 4 pounds or less. My largest breed is the Harlequin, which tops out around 9 pounds. Inevitably, people see one of my Harlies and say, "that's a big rabbit!" I'd love to be able to point to an 18-pound Flemish and say, "No, those are just medium sized. Now, that, that's a big rabbit!" Every once in a while, I do get a call from someone who is looking to buy a really big rabbit as a pet, so who knows? I may add a 6th breed yet!