The most important issue is to make sure the images in your portfolio are your best and only your best! A few good shots are always better than lots of bad ones - ask for other to give you an opinion. When you collect your images make sure you get digital versions so printed copies are easy to make. Make sure your digital images are high resolution for prints and low resolution for the internet and email use. Hope this helps and good luck. Graham
Build your portfolio first then worry about agencies, as you will find your modeling will change a lot after a few shoots, take the advice of the photographer after all making you look good makes them look good, you have potential but not at the level you are now