Hey hey! Yes, it's surely not impossible. the key is perseverance, but at their own pace.
Bandit was a tough cookie as well, neglected etc. and there were many times i thought it was hopeless, she could not be bribed with treats, and barely touched! i tried to train her to step up, thinking that was the first thing she should know, but after I figured out that she'd let me know what she wanted to know first, things got easier. have them get to know a clicker first. It really is the best thing to use to train a bird and i'll fiercly deffend that statement if i need to! just click, and give them a treat, over and over and over again, in - say - 5 minute sessions, twice or three times a day. for like a week or so, then target training, if you can get them to come out of the cage willingly, by all means do, otherwise just point a stick through the bars and click and treat when they touch it. Bandit was very agressive so i spend ages only rewarding her for gentley touching the stick and ignore when she attacked it, after a while i moved on to using my finger instead of a stick to get her used to my hand. spinning a circle is the first proper trick she learned, then high 5 (or 4 in her case) she shakes her head no on command and she's still progressing. stepping up however is still tricky. she knows darn well what i eman when i ask her, but she will only do it when SHE feels like it. no matter how many treats i try to bribe her with
Anyway i hope this helps, the main thing is, don't get discouraged! (and get a clicker

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