Here are my perspectives: (Apologies in advance for a looooonnnng post)
First, in terms of profitability, most breed clubs have fairly stringent Codes of Ethics for members and breeders. For example the (English) Mastiff Club of American has the following requirements for reputable breeders -- intended to discourage 'puppy-milling' -- which reduce potential for making profits:
The Mastiff Club of America requires its members to adhere to the following guidelines which constitute its Code of Ethics. The Club also requires that members, breeders and stud dog owners not aid or abet the violation of these guidelines by anyone else. This Code details certain practices necessary to implement the objectives of the Club as outlined in Article 1, Section 2 of its Constitution.
1. I will consider only the betterment of the breed when breeding a bitch or allowing a breeding with my stud dog, being conscientious of controlling and eliminating inherited problems. A breeder and stud dog owner shall plan each breeding with the paramount intention of protecting the breed, and only when the parties involved agree the breeder is in a position and has the knowledge to give proper care to both the bitch and offspring.
2. I will not allow a bitch to be bred prior to her reaching twenty-two (22) months of age, nor shall any bitch be bred after her seventh (7th) birthday. A bitch will not be bred more than once in any twelve (12) month period unless she does not whelp a litter, the litter is stillborn, consists of a single (1) pup, or as a part of a veterinarians recommendation for treatment of pyometria. Any other reason would need to be stated in writing, along with a licensed veterinarians certification of good health, to be received by the Recording Secretary at least fourteen (14) days prior to the breeding for the Boards approval.
3. I will sell a Mastiff only to a buyer whom I believe to be interested in the protection of the breed and who would agree in writing to provide the highest quality of care for said Mastiff, including quality food, water, proper shelter from heat or cold, active companionship, appropriate exercise, socialization and professional veterinary care whenever necessary.
4. An MCOA member will sell each Mastiff puppy/adult on a written contract signed by all parties. Said contract shall contain, but is not limited to the following provisions:
a. Complete care/feeding instructions.
b. A record of inoculations and worming with a recommended continuation schedule.
c. Provide the buyer with a five (5) generation pedigree on the litter.
d. Furnish a signed AKC registration or transfer form, unless written agreement is made with the buyer that such papers are withheld or are to follow.
e. A provision that ensures that the breeder is contacted whenever an owner can no longer keep a dog at anytime in the dogs life and that the breeder will take back the dog if asked to do so.
f. Stipulate that the buyer have a veterinary check-up within five (5) working days of the sale, (or whatever is applicable in your state of residence), to determine that the Mastiff is healthy. If the veterinarian determines that the Mastiff is not in good health, the breeder will, upon the Mastiffs return, refund the purchase price or replace the Mastiff.
5. I will not knowingly sell or provide a Mastiff for resale, gift or prize or to a broker/agent for resale. I will not engage in the brokering of puppies, (selling or buying), EXCEPT in a case that would prevent a potential rescue situation. ALL SUCH CASES MUST be documented by letter to the MCOA Recording Secretary.
6. I will not sell a puppy/adult who is sick, nor will I ship or deliver to the buyer a puppy less than eight (8) weeks of age.
7. I will show good sportsmanship at all times and in all matters relating to Mastiffs. I will maintain the highest degree of honesty and integrity. I will not knowingly make a misstatement of fact in any serious discussion of my Mastiffs or the Mastiffs of any other Mastiff owner that I might have with persons not qualified to judge the fact for themselves. When advertising my Mastiffs in any media (magazines, internet websites, mail, email, etc.) I will not make false or misleading statements. I will only use a picture of another owners Mastiff with the owners express permission and I will clearly identify that Mastiff and the Mastiffs owner in the ad.
8. I will take back any Mastiff bred/sold by me who has been displaced. If I am unable to do so, I will assist MCOA Rescue or a regional Mastiff club rescue in the placement of said Mastiff. I will reimburse MCOA Rescue for all costs incurred not to exceed three-hundred dollars ($300.00).
9. I will require the neutering/spaying of any puppy/adult I place or sell as pet quality as soon as the dog reaches the appropriate age. The MCOA recommends puppies deemed pet quality to be placed with Limited Registration; puppies whose quality is questionable should be placed with Limited Registration which is reversible, if appropriate, when said puppy becomes more mature and a better determination of quality can be rendered; show/breeding quality puppies should be placed with either Full or Limited Registration.
10. I will not sell, nor use, a Mastiff for the purpose of attack training, fighting, or any other sport detrimental to the breed and its reputation.
11. I will not produce more than eight (8) litters in any twenty-four (24) month period per household nor will I permit my stud dog to be used in a program, which would exceed eight (8) litters per twenty-four (24) month period per household. I will not purposely evade these guidelines by putting my dogs in the name of friends or other family members.
12. I will provide the highest quality care to all Mastiffs that I own, or that are in my possession, for as long as they are in my care including quality food, water, proper shelter from heat or cold, active companionship, appropriate exercise, socialization, and professional veterinary care whenever necessary. I will never abuse, nor knowingly allow abuse of these same Mastiffs.
If a member breeder does not honour the code they can be brought up on ethics charges and kicked out of the MCOA. There are clubs/organisations with by laws and codes of ethics for breeders of many other breeds. I don't know if there is a similar body for Presas. I believe the UPPC uses the UKC Code -- which is quite watered down compared to the above, but still has some expectations about breeders being discerning about where their puppies are going and are prohibited from selling to wholesalers or 'retailers' -- which, broadly speaking would include someone flipping puppies.
There certainly are mastiff breeders I know that I would still consider reputable and responsible who do have 'commercial' operations. Hence they do not belong to the MCOA because they cannot abide by the strictures on numbers of litters per year. But the ones I know adhere to all of the other MCOA ethics requirements, retire their bitches after two litters, and incur huge expenses showing multiple dogs -- and generations of dogs -- to their championships in national and international shows. I don't know any reputable breeder who can count on making a consistent profit over the long term. As I believe we have all learned from our own dogs, disaster can strike at any time. My breeder had acquired particular bloodlines that conformed to her 'vision' and by dint of very selective and careful breeding for three or so generations, produced her 'dream' stud dog. Well, right after his first litter, he got loose and was hit by a car and killed. Many English Mastiff bitches require C-sections -- which are costly on their own and sometimes go terribly wrong; litters are reabsorbed or still born-- as people have already mentioned, you can't guarantee how many pups are likely to be born in a given litter -- could be 16, could be a singleton. Many breeders do ultrasounds to determine this -- another big expense. Puppies die within the first three weeks; dogs bloat; hereditable disorders may suddenly crop up in a bloodline -- forcing breeding programs to be abandoned.
I've never bred dogs, but I have bred, trained and showed Arabian horses. I was a preservationist breeder of some ancient bloodlines. I was in it because I was passionate about it. My operation did not break even for over seven years, and when we finally made some profit, it was because we had expanded our operation to include boarding, training, selling tack and renting facilities for horse shows.
Whilst I would not condone ANYONE flipping a puppy of any breed, in this case we apparently have someone who is selling a Presa puppy to (it sounds like) anyone who will cough up the cash. If it is not someone who knows Presas, this is a recipe for later disaster.