Welcome!
Ask lots of questions, that's the only way you will find your answers.
I would say 1 year. I would question a 5 month guarantee. There
are a lot of people here on this site who can answer lots of questions,
I'm sure they will help you the best they can. I'm not a breeder, just a Yorkie Mom.
As far as food, use what your breeder is feeding, if you change the food
too fast, she will get an usset tummy. There are so many good foods out there,
you are going to have to find one she likes. Just make sure it's a good healthy one.
6 puppies, sounds like a big litter to me, but like I said, I'm not a breeder, so
I wouldn't know.
Again Welcome! We would love to see pictures of your new baby!