Too many sunburns in the past and all those fun racerback tops might be catching up with you!  The most cost effective way to treat these is with an IPL or an older laser called a Q-switched YAG (hard to find these now).  If you go the IPL route, choose an office with a Lumenis One (very powerful which means fewer treatments).   Depending on how many you have, 3-5 will usually suffice.  You will have to use clothing or very good sunscreens though or they will come back with future sun exposure.  Costs - it's very hard to say without knowing how much area you want done and how dark the freckles are.  Schedule a consultation for a price estimate before you commit.  Dr. I