Try to be reasonable with them. if they cannot sex it, ask them if you bring a vet will they let the vet sex it.

Don't let them fool you with their "claims" a vet won't for fear of hurting the snake, they just want to move the animal fast and if you have it sexed and it is male they know they lost the sale.

I saw a 1300 gram normal go for $220 at auction tonight. Breeding size females go for a premium price during the breeding season, so if it is a female, you could do worse than spending $160 on her. Of course, you have to see if you can find a vet willing to sex it, and how much they will charge you. Your best bet might be to talk to the vet the store uses, you might get it done no charge then.

Gale