This article here explains the breeders pricing
http://www.malteseonly.com/prices.html
You may say you still won't pay that much for a dog, so you find one from a byb in your price range, an improperly bred maltese can have stifle or patella problems so your $800 purchase pup will now need $3000 worth of orthopedic surgery to walk properly and be pain free if the defect is only in one leg though most have both legs affects your pup could now be a $7000 dog without even factoring spaying /neutering, heartworm wellness testing and vaccines . Other health problems can include shaker dog syndrome and portosystemic liver shunt, when responsible breeders sees this occur in one of their dogs or offspring the breeding lines are ended, a byb breeder is out to make money so does not care, so you could up at about a 10 months after buying a pup, seeing it become very ill, hundreds of $ later after testing is completed learn the way to save its life is through surgery.
If you still want to take the gamble on a "bargain" price pups check Kijiji.ca and make sure to set aside a savings account and bank $200 a week the first 10 months to ensure there is money available for vetting just in case it would give you $8,000 to cover spay/neuter vaccines, possible dental in a years times, and should be enough to cover potential liver shunt "or" leg joint surgeries if needed, you could check out vet insurance but make sure to learn what exclusions they have, they may have limits both annually and by procedure, many won't pay for inheritable diseases so it could end up being an added rather than a savings. Paying more for a pup initially by going through a reputable breeder can often be the far better bargain in the long run.