ok.. nice hypothetical game
1 male and 1 female Normal corn snake. Assume they were purchased as babies and paid $20 each, so $40 for two baby snakes. You got lucky and go them CHEAP (no tacked on shipping costs and other stuff).
Food costs vary. Most people with only 2 snakes are not going to buy food in bulk-frozen so they will go to a pet store or find a friend to split mail order costs. Anyway, let's just assume an average ball park figure is that it would cost an average of $100 to feed 1 snake for 1 year. Give those two snakes say 3 years to reach a nice safe breeding size....so 3 years of food for 2 snakes = $600
Typical pet owner would house the babies in a 10 gallon tank (they are cheap and easy to come by compared to more expensive custom/specialty cages). Since many corn snake experts insist that snakes be housed separately to prevent "accidents", our hypothetical owner purchases 2 tanks for their babies. Then there are all the necessary accessories that go along with it..substrate, lights, water bowls, tank lids, etc. Assume each set up cost oh.. about $100. So, 2 complete baby tank sets = $200.
Over the course of 3 years, baby snakes grow up, more substrate is purchased, etc. It's also time to up the tank size. For economics sake, assume each snake was moved up to a 20 gallon tank. Add in another $200 for these upgrades and maint. costs.
Ok, babies all grown up. Time to start breeding. Let's buy nesting boxes, nesting material, incubator, etc. Add in another $100.
You've already put in an estimated $1,140 into these two snakes over the course of 3 years and have yet to figure in the 3-year cost of the heating, electric, & water bills, your time in cleaning cages, feeding, gas/driving, etc needed to help support your pet owning activities. For convenience sake, figure $100 per year (it's probably higher though).
Now we are at about $1,440 to maintain 2 snakes over 3 years. Some things may have been overestimated, but others were grossly underestimated, so this figure more or less balances itself out. There really is no way to be fully accurate here due to the many options available and ever-changing prices and choices different people tend to make.
Ok, average clutch size for a corn snake is a 12 eggs. Assume by some lucky chance your snake double clutched during her first year at breeding, expect maybe another 8 eggs. 20 eggs total in one season. Assume all babies survive to hatch out nice and healthy. Remember, these are NORMAL corn snakes - no fancy morph or hets or anything.
To attempt to break even for all that you put into your 2 snakes over 3 years -- you decide to sell the 20 babies. To do this....the price you would have to set would have to be $72 for each baby.
Is it any wonder why you CAN'T make a profit off them?
Who in their right mind would want to pay that much from a no-name first time hobbyist breeder? Then don't forget, the longer it takes you to sell those babies, you still have to support them with caging, accessories, food, etc. What if you sell to someone who wants them shipped? The price goes up over the $100 mark for that normal baby corn. If you give any of the snakes away, you are putting yourself deeper into the hole instead of trying to break even like you hoped.
You think you can continue to breed for a few more years and it might all magically work out.. not likely. You still are maintaining those 2 adult snakes, food costs, heating bills, maint. costs, etc. plus you are also supporting any babies that you didn't sell the previous year or perhaps you held some back to raise some up to breed in the future so as to expand your colony beyond just 2 adult snakes.
You sell to a pet store.. heck they have their overhead costs to think about too. They are actually out to make a profit. They are going to want your snakes as cheap as possible in order to give them a reasonable mark-up. You can also be sure a lot of pet stores DO add in what it cost them to have the animals shipped to them in the first place. And again, they still have to support that animal until it is sold. There is no guarantee it will sell within a week or two.
Unless someone is lucky enough to be at the top of the pyramid scheme of a high demand, low supply animal where you can justify upping the price of the animal to meet and exceed your operating costs, there is just no money to be had in selling animals.
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PHWyvern