Please remember these prices were years ago and each vet has different pricing, both of these were in CA:
ATB nose abscess small removal, antibiotics $400 (2012)
Boa nose abscess removal surgery, antibiotics $750 (2003)

The vet should quote you before doing anything and that should only cost the office visit fee which can also vary depending on vet (~$25-65 seems to be the average, mine are usually $40-65) and as mentioned, ensure your vet deals with exotics, having worked with reptiles before is a major plus.