Andy,
I know of only one person that makes a living from breeding dogs and doing it right. there are several considerations. One is the breed and average price per puppy. Litter size will affect the expectations of the value of a litter. For instance if the breed sels for around $1000 a puppy and the average litter ize is 6 you are looking a round $6000/litter.
There are some things that you can do to increase the value of the puppies. Dogs bred form Conformation champions will be more valuable than dogs from non-champions. In the working breeds a working title will also increase the value of the puppies. From conformation stock you will get 1-2 show quality pups per litter and they will be aproximately 50% higher in price (providing you can pick the proper puppies). Getting the titles requires a significant expense in terms of time and money. If you don't handle you will also have to pay a handler to take the dog and handle the dog in the ring. So add entry fees, handler fees, and travel expences. In the protection area, you have an even bigger comitment of time, training, and trialing with costs for entries and travel.
Now start factoring costs. One an adequate area for the number of bitches required to maintain a comsistant income stream, keeping in mind that a bitch can only really be bred once a year. In addition they won't take every time. So figure 10% more dogs than just what it would take to maintain the income stream. You will need both housing space and exercise room for the dogs. That would take a significant amount of space. In addition you need to consider what you will use for stud dogs. Are you going to use your own or go to outside studs. In one case ad the costs of maintaining the Male(s), or the stud fees for the breedings (generally the value of 1 puppy). Males may create some increased revenue by stud fees. You would probably need to have at least 3 Studs to maintain your own breeding program.
Kennels aren't considered great neighbors, so you will probably need to be a bit out of town, or at least in a more rural area.
The kennel can provide some additional income by boarding and training. However that carries some addition risks of bringing diseases in that your dogs may get. These things require addtional room and expertise.
Now figure the cost per dog per year for feed. Then multiply that by the number of dogs you are going to keep. That is going to get expensive.
Plus to take care of that many animals you will probably need help. Kennel help is one of those things that you will get what you pay for. Help just feeding and cleaning is a little cheaper, and if you have the space you can also provide room and board for a portion of the cost. Trainers are going to be more expensive and generate some additional income from training.
So all in all the one person I know of that breeds dogs for a living, (no aditional income, just breeding dogs) keeps 15-20 champion bitches and 3-5 champion stud dogs. Lives on a large "farm" in a rural area. She is the top breeder of Giant Schnauzer Champions in the US, having bred over 1000 champions. Most of the other people in the breed don't like her much. Many are very proud when they can have a pedigree free of her dogs. I doubt that you would really consider her rich, but her place as a high value based on the area where it is, and the amount of acerage involved.
I would think that it would be tougher to maintain a high level of income from breeding working dogs based on the fact that putting the training and titles on the dogs requires more time and expense to get the titles. Plus it is going to be more difficult to work that many dogs at one time and do it well.
That is without even talking about Vet costs, and the occasional C-section. The cost of a C-section will just about wipe out the entire value of a litter for the surgical expense.
If you can't be a Good Example,then You'll just have to Serve as a Horrible Warning. Catherine Aird.