You might want to practice breeding techniques with an easier species, like your kingsnakes, but that said, I don't think Mandarins are too hard. I wouldn't try breeding them at an early age, however. I'd wait until they are about four yrs. old, at least.
There are Mandarins from different locations, which look and behave like different subspecies. Lora knows her stuff and has some nice Mandarins, but there are some from other breeders which are nice too, and you should shop around for the best prices. You can get CB for as low as about $250/ea, and I don't think anyone should pay more than $400 for a normal speciman at this date.
Here's a juvenile Sichuan mandarina I got from Rex Knight who has some great snakes and is a good breeder....

Mandarins are montane and are active mostly at night. They hide during the day and are rarely seen. It's like keeping a large milksnake. They are hardy and cool adapted, conditions easy for me to reproduce in n. Michigan. My room temp range is 68 to 82*F, with higher end temps in summer with lows in the low to mid-70's. Herp Room humidity is usually in the high 40's, but can get higher or lower. I use aspen shavings and paper towels/newpaper. The snakes normally have a dry hide box, but I often use a moist hide when they go into the shed cycle as they can have shedding problems if too dry. My Mandarins are doing great under these conditions.
Good luck with these great snakes....TC.
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Ratsnake Haven: South Korean Dione's ratsnake, bimaculata phases, mandarina locales, calico and hypo taeniura, Western and Southern Plains ratsnakes 