You are correct when there are varying cost for periodontal treatment and you should be prepared. In regards to cost it could be as simple as let''''s say $500 or as much as $1500. In regards to your pocket levels and treatment with antibiotics, periodontal disease cannot be cured with simple antibiotics due to the nature of the infection. Deep pocketing harbors bacteria like the barnacles in the open sea. It is literally impossible to treat with antibiotics because your mouth is an open source for reinfection. The first goal of periodontal treatment is the non-surgical debridement of the pockets to decrease inflammation and to allow some reattachment of the gum to the tooth root surface. When the first phase is completed and pocket still exists with bleeding, sometimes the dentist or periodontist must employ surgical techniques to reduce the pocket so that it is manageable for the normal oral hygiene techniques. In any case, your dentist must inform you of all potential financial implications, but also be aware that once you are on the path of losing the bony supporting structures for you dentition, you do not get it back. Try to treat it early and it will service you for years to come. I hope this helps with you dilemma.