Teaching English

Hi,
I got a teaching position in China, but I was told that we need to apply for the working visa and working permit there. So me and my husband are going with the tourist L. I was also told that we need to pay for an agency so they can apply for us for the papers (since we are not English native speakers). Is that so complicated, isn't there anything we could do from home? Do we really have to pay for that agency?
Thank you!