Welcome Laura!!!
It makes sense to minimise paying out whilst you start out and you can do so on a very small budget. Yes, amateur pics are fine. I have been using amateur pics for ages and this did me no harm.
It's all about marketing the whole package in my book, and whilist pics are important it's also how you promote yourself, which criteria you fall into, where you are located. So many factors to consider and with this work, unfortunately, you don't just learn beforehand, it's more as you get into it with time and you will see what works for you and what, if anything, you specialise in or feel comfortable with.
I wish you luck and yes this site is wonderful. Many of us would be lost without it, me included!
Love
Alex
P.S Bloody hell, it's supposed to hit 32 degrees in the week! Still should make the guys more horny so not all bad hey!