I am about to start my covering letter for 'Knowing Abbie'. I've been reading examples of letters that have resulted in agent contracts and will also be rewriting the letter I wrote for my last WIP.However, I read an interesting website about covering letters and what to include. There should be a paragraph describing publishing credentials.What sparked the 'or not' in the title of this post comes from a different article that offered common query letter mistakes from Writer's Relief:
Mentioning prior manuscripts (and/or certain self-published books). If you’ve written three unpublished book manuscripts in the past, best not to mention them. Otherwise the agent in question may be intimidated by your prior projects, thinking, “If I take on his/her current project, the writer will probably pester me to represent all those previous books that, for whatever reason, didn’t sell.” The same goes for self-published manuscripts, which agents will look at the same way as unpublished manuscripts UNLESS you have significant accolades for your self-published book.
I've read other articles about covering letters that suggest it's okay to mention self-published works.What are your experiences? With the rise in popularity of publishing platforms like CreateSpace, SmashWords, FastPencil and others, do you think it's appropriate to mention self-published books in a covering letter?