My mom really wants a snake of her own, so I'm thinking for her Christmas present, I'll get her her very own snake. I'm trying to figure out the best kind for her.

I need a snake that:

Will stay small (ideally that can stay in a 10 gallon tank)
Is calm and easy to handle
Easy to care for (good eater, no fancy requirements)
Is relatively inexpensive

She is in love with my sandboas, perhaps a male would be a good choice, but any ideas are welcome!