First off congratulations on your possible new addition .

I am a multiple dog Mama and i personally dont have any trouble at all with the dogs fighting, there is the occasional telling off (Eg Elvis standing on Clover when she is asleep, and Clover snapping at him) but never anthing serious.

Introducing new dogs into the home can take alot of work but in some cases it is very easy. I always like to introduce new dogs the the first dog on neuteral ground away from the home say at a park or at the Shelter (If a shelter/ rescue dog). Let the dogs get to know one another and play if they want to. And most importantly always supervise the two dogs when you bring the new dog home.

As for food dishes each dog should have their own, i would start off by feeding the new dog in a seperate room/ area untill both dogs are comfortable with one another.

The dogs should work out who is Alpha over time, try not to interfere much at this stage unless it is realy nessescery.

You have come to the right place and you should get some excellent help from people here.

Good luck with your new dog search.