Resume and Agent question

I've been submitting to agencies in larger markets for a couple of months now, but I'm taking it slow. The reason for that is, I'm not sure how much emphasis is put on the "resume" that they usually ask for in submissions.

I have some credits, but not many and nothing anyone would recognize. My question is whether I should wait to submit for large market and boutique agencies until I have an extensive resume, or should I just start submitting everywhere?

NOTE: I have professional demos, and already have a local agent. I have everything I need, even the resume. It just doesn't have a lot of credits on it, and no IMDB credits. I can book work, but I hate the thought of working $5 gigs on V123 just to build a "resume".