It's actually very useful to sex a bird, quite inexpensive and not hard at all because all you have to do is request the kit from one of the online labs, bring the little vial they send with you when you take your bird to his first AV check-up (and this should be done almost immediately after you bring it home) and ask the technician or the vet taken the blood sample to just take a bit more and put it in the vial for you.
Please make sure you have different types of soft foods for when it comes home as well as feeding syringes or pipettes and a scale. They tend to regress when they are moved and you need to be prepared for it.