If you have a adult female, 72 x 24 x 12 (6ft cage) would be a proper size, and if you have a adult male a 60 x 24 x 12 (5ft cage) would be good. Average size for female is around 7.5 ft to 9 ft and a male 6ft to 7.5ft. Humidity is around 50 to 60% on warm side. Low ambient temps would be around 80d and high basking temp around 88 to 90d (can be as high as 92d). That is a good price for a healty 6 month old rtb.