They cost about $20.00 shipped to your door for 100. They only eat mulberry so unless you have access to a tree youave to buy the chow. They are like all the feeder insects, they eat and poop, eat and poop and it is constant maintenance cleaning out their containers. The silk breeders sell these things called pods and the food is ready made and it comes with the silks but I think the most is like 50 in the pod. You turn the pod upside down and the poop is supposed to fall to the bottom which is the lid and is supposed to be easy clean up. Well they spin silk in the pod on this little trellis thing that comes with it and all the poop gets caught up in it. i don't like the pods and order the chow seperate and then put 50/50 in two containers. Normally they have been pretty hardy for me and grow at a decently slow pace but lately I have been getting alot of die off. They are a great feeder and they are gentle and don't bite! Sometimes I feel guilty feeding them off! They are supposed to pupate after about 5 weeks but I have had only one spin a cocoon so far. It turned into a moth after about 2 weeks and I fed it to my cham. Some people breed their own from the moths but I have never gotten that far. You can order them online from Mulberry Farms or Coastal Silkworms.