I am considering changing from keeping a bull to AI. I have had one bull go sterile then the next bull scattered the calves over a 4 mth period. I have a small herd approx 20 cows. How much work is involved in this? How cost effective is it? Do I have the vet come out or take that cows to the vet? Can someone else than a vet do this? How hard is it to syncronize the cows?Any help and suggestions would be appreciated.