They are GREAT! I got my hubby into BDs about 4 years ago. Our first breeding happened without us really trying. We were niave, we just said "Hmm... I wonder what will happen if we put them on the rug together, will they fight?" NOPE! They did something, but it wasn't fighting!! Before we knew it we were breeding BDs! We now have 9 breeding adults, 4 sub-adults and hundreds of babies!
If I were you I'd start out with 2 normal BDs. They are easier to sell to local pet stores and distributors. Once you get into morphs, if you really want to get your money's worth, you need to sell them online, individually, or at shows.
Each female can produce up to 40 eggs a clutch. Most of our females have at least 3 clutches a year. You have no control over how many clutches she will lay, they only need to breed once. They store will the sperm. Although, it is better to let them breed more than once over the season, you'll have a better chance of getting more viable eggs that way. We have a 98% hatch rate and use an incubator we built ourselves out of a large cooler. If you want to know how let me know.
As for temperment: Alot of babies and juveniles have little attitude problems. The threaten, etc. They get over it. They need to be handled and spoiled a little. We have one male (a bright orange morph) who is HUGE, over a year old and still has a major attitude. All of our others are fine. When we first got into BDs we would be afraid of the little ones trying to bite us, now we laugh at them and pick them up anyway. They normally have GREAT temperments.
If you are looking for good babies there are tons of places to look. If you are anywhere near Mass or NH we will be selling at the next NH show. We have 5 "hold-backs" who are sexable. Their parents were really pretty (Angus and Athena - if you look on our site). We'll be keeping one or 2, but the others are available. We also have some other babies (unrelated) who are very well started 10 week olds, but they aren't sexable yet. Like I said, if you'll be at the NH show let us know and we'll hold some good ones for you. (We also ship, if you're interested).
Otherwise, I highly recommend breeding BDs. Its fun, easy and addictive!
Good luck!!
Kelly

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Kelly Affonce
DeKeaff Exotics
www.dekeaffexotics.com