What is damaged on the 'new' used PC? You may be able to turn both broken machines into a reliably functioning PC. Also, consider reaching out to a local charity to get help fixing it if you're unable to do so on your own, either b/c of your disability or financial constraints. And it might be handy for others willing to help you out if they know where about you live. Town and/or State/Province (if you're Canadian ) suffices, IMO.