I'll tell you its a 7 day a week task and requires a serious commitment. don't think you're gonna get them and throw them a skull once or twice a year. To keep them alive and thriving, you need to watch humidity, temperature, ventilation and keep them well fed.
It's not too hard during summer months because you can keep them in a shed or outside and they love the climate. They don't multiple very much when there inside during the winter because 72 degrees isn't suitable for them. Feeding them is cheap and easy.
I keep them at 80 and they breed like gang busters during the winter with all the food they get.
I keep mine in a chest freezer with thermostatically controlled heat and continuous ventilation to the outside. The bigger the colony, the faster they can remove the flesh from a skull. A full unprepped coyote skull in my colony takes a day, a prepped deer a day and a half.
Don't let any outside bugs in the colony as they can destroy all your hard work pretty quickly. This means freeze all meat before it goes in for a day or two to kill any parasites, fly eggs, etc that might be on it. Roadkill sounds easy for food, but make sure it's skinned and frozen...sounds like fun doesn't it??
I buy a big pack of hamburger from the grocery store when it's on sale and keep it in the freezer. I feed them a small chunk every week. Probably costs $2.00 per month to feed them. I freeze all animal skulls before giving them to the colony for cleaning.
2.5 weeks?? Bet that smelled good by the time it was done.... I think an unprepped deer in mine might take 4-5 days tops. If you were keeping your colony, feed it a LOT more than you are and it will grow any time of year. Also, you need to keep your temp up near 80, that helps too.