I'll respond to just about any Armslist email if they can put together structured, coherent sentences and at least make an attempt to use some punctuation. I will even politely respond to low ball offers if the guy seems legitimate. People with no grasp of the English language or a blatant lack of any adult type ability to communicate their thoughts will be ignored. It's typically worked well for me. The serious players usually provide at least a first or sometimes a first and last name in their initial communication.