Quick general question. Say you've got this great manuscript with a strong multi-cultural theme. And you find an agency that has a history of repping multi-cultural books. It's the perfect match. Good for the agency, good for your book.
But what if your next WIP is scifi? Or horror? And on the agency website they say not to query them with those genres.
Would your potential new agent be able to muster up the enthusiasm for your next book? Would the agency even want to represent another genre?
Perhaps I'm over thinking this, but are there cases where you'd turn down a perfect agent for your book for the sake of a better agent for your future?
It's not bad to think long term, and to look at your interests. But unless you've already written those future books, you can't know what you will write next.
Many agents will represent anything of yours that they feel comfortable they can sell, including books that are generally outside there usual areas. But there may be circumstances in which you write something your agent doesn't think they can sell, and they will refuse to shop it (and sometimes for reasons that are good for you, and then they will help you find someone to represent that book they can't represent well) - you will then need to look at your contract and talk to the agent, about your options, about why, about whether you will shop that yourself or find a second agent for that genre, etc. But I think it's hard to look into the future and know what will come.
Now, if you have already written 5 books, and 4 are vastly different from the 5th - ie, 4 fluffy middle grade novels and then 1 dark adult literary novel - well, chances are you will need a second agent - and chances are your agent will refer you to someone for what they do not represent.
But if you usually write contemporary realistic YA and then write a paranormal adult romance, well, that might not be as far a stretch - depends on the book, on the agent, size of the agency, etc.
So, if you know you have an interest in two different markets - it might make sense to focus on agents who represent both markets or who are at a larger agency where other agents in the agency rep the market your target agent doesn't rep.
But if you have an offer from a great agent for the book in hand, and no other books currently at issue, I'm not sure it makes sense to turn down that great agent for possible future books. And you can always change agents later if your career takes off in a different direction. But to stay stagnant now, for hypothetical future books seems silly to me.
And if you have several books done - ie, those 5 hypothetical books above - wisdom generally says to shop the strongest, but you also might want to consider if that one book is a one shot for you, and your heart really lies with the other 4, and whether you should really be looking for the agent who could best rep the kinds of books you intend to continue to write.
~suki