Welcome to the community, Kenshow! My advice is to start with foam. it's widely seen as a good "beginner" method. it's also better to start with because you don't need to have all the (expensive) safety equipment and overhead that you need to work with resin and fiberglass. it's also easier to "bully" into place, compared to card stick. you can make lots of mistakes that EVA foam will stretch or scrunch up to accommodate. It's also WAY lighter than resin/bondo, and actually insulates heat REALLY well. it's also generally more comfortable. it tends to bend and flex, instead of digging into you. As for buying it, this is what i buy. bought about $70 worth in 2014, got me through an Iron Man Mk. 6, a War machine suit that had to have half of it remade because of scaling problems, and i still got a few sheets around, so a little goes a long way. hot glue works the best on it, which is even cheaper and more easily accessible. i got more tips and tricks for foam, but this is about as much i can think of relative to what you're asking for. hope it helps!