£50-100 would be about right, you maybe able to get on from a local breeder cheaper or from a shop for a bit more
Have a shop around and ask lots of questions
1.0.0 normal royal 1.0.0 mojave royal 1.0.0 pastel enchi royal 0.1.0 cinnamon royal 0.1.0 pewter royal 0.1.0 genetic stripe royal 0.1.0 lesser goblin royal 0.1.0 phantom royal 0.1.0 Columbian rainbow boa 0.0.1 aru x jaya GTP 0.1.0 bredli 1.0.0 trans pecos rat snake 1.0.0 fat black cat