12weeks; no earlier. Neutering before 12weeks can cause incontinence in the future.
Yes. It's the smart thing to do if you don't want them humping, spraying and running away to look for female dogs in heat.
1 day is what happend with my friends dog
When your dog still is a puppy like around 6 monthes or 1 year old the sooner the better.
My answer is... About a year because when their puppies they are small and fragile. If you did already do this and they cried then wait for a year or so. With all due respect, there's no need to...
6 months