Why is there such a vast difference in price of PRP?

The price for any cosmetic treatment is dependent upon the doctor's philosophy of practice. Some Physicians purposely keep their price reasonable so that many  people can find it affordable  . Additional factors include the number of patients the doctor's office services and thereby, the cost of goods. If a doctor is very busy with PRP, he can purchase the necessary tubes and other items at a better price. I recommend that you don't shop for price but look for a PRP expert who has good reviews and photos.
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Price can vary due to skills, expertise and technique of the practitioner. In our practice, we combine prp with progesterone to get great results with hair regrowth. Keep in mind, it will take up to 6 months to see improvement. See an expert. Best, Dr. Emer

Cost of PRP depends on many factors including the kit used in the treatment, and the expertise of the injector.

Thank you for your question!
The cost of PRP depends on the cost and quality of the tube used for spinning the plasma, the time and technique of injection or needling, the amount of material injected, the cost and time of numbing the skin when needed, the time to explain the use of adjunctive creams and lotions that promote better results and quicker healing and the difference between physicians who do this regularly and command higher fees and less experienced physicians wanting to build their practices.

PRP procedures vary in price due to the areas being treated, the quality of the PRP (beware, there are vastly different concentrations and variables to "PRP" treatments, pick a very qualified provider), and then skill and experience of the physician.  But $8,500 is very high!  

The cost of PRP depends upon a number of factors such as : Experience of surgeon, the kit he is using for the PRP preparation, his results, and whether he is doing any procedure in combination to that or not. So, thats why you will find this variation in the cost of this procedure.

Amount of PRP used, method of preparing prp (fda approved machines or basic llaboratory centrifuge), experience of the provider who is performing injections, inclusion of Acell or extracellular matrix.   I typically charge $4500 for 3 treatments, 1 including Acell.   It is a time consuming procedure to perform correctly with expensive disposable costs.   

There are different systems out there for preparing the PRP.  Depending on the system the cost varies.  $8500 is way too much unless something else is being done.