I can't access Recovery mode to erase HD

I can not access the recovery mode. If I reset my MAC while holding "command-R" it just brings me to the desktop. If I reset holding "option" it will show me the HD but no recovery option. If I access the disk recovery from the desktop, any option to erase HD is greyed out. I have done all system updates and I can't access the internet recovery option either....

Please help, I'm planning on selling my Macbook tomorrow!