Rules for using commas http://www.englishclub.com/writing/punctuation-comma.htm

To be grammatically correct, the second to last and the last adjective that describe a noun needs to be separated with an "and". So the grammatically correct sentence would be "the eccentric and fact based seller...". If you have more than two adjectives, like "the eccentric, abnormal, and fact based seller" you would have a pause between all the adjectives other than the second to last and the last. So in this case, the pause would be put between eccentric and abnormal.

I'll respond to your question, and correct it as I go: - "I think there should be obviously a pause between these words. I use "/" to mark it. [If there isn't,at least, couldn't read them too closely]." I disagree. This is a series of adjectives. I wouldn't put in a full pause here - it'd sound like you'd forgotten what you were saying. The text in the brackets [ ] doesn't make sense. - "I'm not sure about this. If either my thought or the sentence I have written is grammatically wrong, could you please correct it?" The word "writted" doesn't exist. - "I tried to attach a recording here, as I think he gave a wrong pause. If you could, please listen to it, and check it." Who is "he"? - "I'm confused, where can attach the MP3 file?" You add recordings to the Notepad entries. If you wish to add an MP3 here, then you need to upload it to another website and provide a link. Hope that helps.