When it comes to obtaining a particular species, I let my conscience do the work of making my mind up. There are number of things to consider in addition to the ones you have mentioned above such financial, emotional and above all, is it meant to be like this? If its rare, I'd probably not have it because it might not make it under my care. Although, I might be able to provide it with whatever it needs, even water from the heavens. I wouldn't do it. I find myself stuck in situations like these and with the battling thoughts n my mind. I simply turn my back to it and tell myself, I have a good number of orchids growing at home and this is not the end of the word that wouldn't let me buy another healthy one to add to my collection.