IBD kill a ball python in a matter of weeks so if she has been housed with Boas for a while and has not shown any problem it is safe to say that IBD is not an issue.

Now as far as getting her to me it is not buying an animal but a rescue mission.

If this person as such poor husbandry practices there is no telling what else can be wrong, mites, BP being stressed, BP not eating, RI etc.

Do you even have any guaranty that this is a female???

I will leave it to this is saving money worth having to deal with possible problems and taking risks? (only you can answer that)

Now would I take her? No thank you!