I agree, if you're looking for a "good investment" there lots of other, more sure ways to turn a profit. Breeding animals is not a sure thing, you have to invest a lot of hours of your time, and money for the best food consistently, and the best of caging, and there is no guarantee that you will ever produce any babies, or even that your female will survive breeding, being gravid, and delivery. What is your experience and skill level for producing boa babies, have you produced any so far? If you haven't then I wouldn't count on producing any babies for the first couple of years until you get your husbandry all straightened out and you know what you're doing.
In my opinion you shouldn't be breeding boas if a "good investment" is what you are looking for. Certainly a $500. boa isn't much of an investment at all. In the 4 years it would take you to bring babies to market for any female, they price of the same boas are likely to be the same as a normals. Even if you have the 5K or 10K to buy a more investment-worthy boa you'd still face all the above factors, and the price would still be dropping the whole time your boas are even getting to be old enough to produce.
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Caden Chapman
slithering.serpents@gmail.com