I got an apartment through a similar organisation called Circle. It was the answer to my dreams and I have my apartment for life but like you said you cant buy them out. This is a problem for me as I want to own my own place eventually so unless they change the rules (which they might but doubtful) I will be giving it back when I am in a position to get my own mortgage. Its a pity really as my rent is affordable, I love where I live, the organisation is well run and the properties are very well maintained.
I accepted my apartment as I was living in cramped conditions with my daughter so had no choice really but I was one of the lucky ones at the same time. I was waiting just over a year. I actually got refused from Cluid !