Compare the taurine on commercial packaged ferret food, it's really not known exactly how much they need
Yes, most dog foods are high in grains or vegetables which ferrets cannot digest. They do not have the appropriate fat and protein rations nor do they contain taurine, an essentil nutrient for ferrets.
Ferrets do no need their anal sacs removed, it is considered mutilation.
Red bull contains taurine.
What makes dogs different from ferrets - everything is different between dogs and ferrets. Ferrets are not anything like dogs, there would be too much to list here. You need to read and learn about what a ferret is.
You can conceivably overdose on anything if you consume it to beyond a point of sufficiency. Particularly considering that taurine is found in energy drinks, which are incredibly easy to overdose on, it could be assumed that taurine is dangerous in massive quantities.
For five ferrets, the largest cage you can afford as ferrets need room to move and exercise. Ferrets also need plenty of supervised time out of the cage for their health and welfare See related question and answer below for more information
Ferrets should have access to food at all times. Ferrets can weigh anywhere from one to five pounds, too many variables to say how much 2 ferrets can eat in a day
Ferrets would need webbed feet to become semi-aquatic like the mink
It depends, usually about 100.00 US dollars per ferret, older ferrets may be less, as bonded ferrets that need to stay together may also be discounted.
Bathing strips the oils from their skin - Ferrets do not necessarily need baths - if you choose to bathe ferrets it should be no more that 2 times a year. from another contributor: if you bath it to much it takes the moisture from its skin plus the more you wash it the more it will smell
Ferrets are nocturnal and they normally sleep 15-20 hours a day. Ferrets need daily activities outside their cage of about 4 hours
There are numerous dangers to ferrets, You have to ferret proof their environment, ferrets need to be handle by a responsible person (no small kids), ferrets need a special diet, they are carnivores (meat eaters) and cannot digest fruits or vegetables. Ferrets can be prone to illness and disease if not taken care of properly. They could be perceived as prey by some dog breeds.