Vacation days are not for sale. You could have got more vacation by upgrading, but I see you're already a diamond member, so, I'm afraid there's not much you can do.
Vacation
Due to illness I have used up all of my vacation time I need to buy more vacation time because I am not well yet and will miss several days and don't feel that it's fair that is games because of illness How and where do I add more vacation time and what is the cost
Upon joining everyone gets seven days there are no bumps, anymore, for upgrading. http://support.chess.com/Knowledgebase/Article/View/26/0/how-does-vacation-work--how-much-time-do-i-get
Nor upon renewal. http://www.chess.com/forum/view/general/vacation-time7
so i will get 2 days more each month not bumping for diamond platnum is dumb that is one of the main reasons i pay so much to be here its also lame to not be able to purchase more days i have serious health issues and dont think this policy is fair to the ill if i was just lazy yhat would be different but i have serious health issues and need to be gone some times for several days at a time this should be rethaught so as to be more compliant with americans with disabilities act protocols
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I think you'll get more vacation days if you buy diamond membership for one more year.Assuming that it is possible to buy membership for future year, now.
my new solution is i only play games with 14 day moves i will re aquire my vacation time but not selling it is really a LAME idea who thought up this dumb idea
Due to illness I have used up all of my vacation time I need to buy more vacation time because I am not well yet and will miss several days and don't feel that it's fair that is games because of illness How and where do I add more vacation time and what is the cost