Can you Raise Giant Schnauzers, along with Minature Schnauzers?

Dont see why not. 
Dont understand the title though? 

all the title ment was that i was looking for another dog, a large dog for the back yard, and i wanted to allow it inside as well. I talked to a lady the other day that had Giant Schnauzers and she didn't want to sell me one because i have a minature schnauzer that lives in the house with me. I was thinking it was what she thought. and maybe somone out there would give me there thoughts on it sence i have no idea.
I know i love the breed large or small.
I had to put my large dog to sleep last weekend the 23rd. she was very old and sick, and couldn't be saved.

Its possible the breeder didn't want to sell you a puppy as it would be living outside. A lot of people do keep their dogs outside, but usually they would have more than one dog. It would be a lonely life for a single pup outside on its own all day/night.

[Quote;- all the title ment was that i was looking for another dog, a large dog for the back yard]

Sorry but I wouldn't have sold you a dog for your back yard either.  You have one live indoors with you and you want one to stick outside on its own.  Poor thing, why can it not live indoors with your other dog, or more to the point why does your back yard need a dog?

I agree with the others. You were probably turned down because of the dog being kept outside. I know keeping dogs outside is much more common in the US where you are and almost unheard of in the UK, but it's still the most likely explanation.

Awhhhh you guys. Maybe i didn't give you enough information.........My back yard dosn't need a dog....lol. My husband drives a big truck for a living and all the kids are grown and out,So i live alone and feel better with a large devoted dog to gaurd me,and let me know when things arn't right.My back yard is a half acre with a 6 foot tall fence all around. Shaded in the summer green grass and lots of room to run and play. I would never leave a animal outside all the time to be lonesome.I made it clear to the breeder that he would be outside but inside with me most of the time, sence i work from home. But when i have to leave to go some place i would like to be able to put him out side. MY out side dog loved being able to sleep inside at night and play outside during the day. the breeder was mostley concerned with the size diffrence in the to dogs, mini versis giant, she didn't think it would be a good match. i have never had a problem with that. MY big dog that got sick from old age didn't mind  my little dogs being around her, and she never tryed to hurt them. This is my second set of Schnauzers i raised 3 other from pups that died of old ages. I have always raised my big dogs with my little ones.

I got what you were saying. :-)  I think being honest the giant is a lot lot bigger and stronger than that minature and not just in size, the minatures are a lot softer in nature. they are like two different breeds altogether to be honest.    I think it is always advisable not to leave a large breed alone with a small breed also so that would have been my concern as the breeder. The giants are used for guarding and policing are they not.

Why not consider the Schnauzer  ( the middle one).