I’m sorry to hear that you are considering selling off your collection of about twenty Masdevallias due to being unable to get them to bloom, it may well be that you have purchased really young divisions which are not yet blooming size or that your growing conditions are not suitable for them, remembering they are cloud forest dwellers and as such need similar growing conditions, I have emailed you a more in-depth answer, however if you feel that you still want to sell them, yes I would buy your collection.