China Visa cost details

Hi, myself and a friend are going for a holiday in Vietnam. We are from Australia and are flying to Hanoi via Guangzhou then returning the same way. On the first leg of the trip, we will not be leaving the airport in China as there is only a 4 hour wait, however on the return leg we have a 9 hour wait. We would like to leave the airport and see Guangzhou for the day. As we will only be leaving the airport once, I assume we will only need a single entry visa. Is this correct?

Also we live in a regional area so would be mailing our application and passports to the chinese consulate along with a return registered post envelope. What will the cost each be? Is it $40 for visa + $55 handling fee ($95) or is it $55 ea total? Also if it is the first option do we both need to pay the $55 handling fee or just one between us?

Regards, Andrew