Two Scottish parents visiting teenage son studying in Tianjin in February 2017 - visa application.

Please could you assist - our teenage son studying Mandarin in Tianjin on scholarship till July 2017 he has Chinese student X type.
We (parents) would like to explore China with him in February 2017. We think it would be for a maximum of three weeks leaving from UK to land in Shanghai then travel up through Xian - see Terracotta Warriors - then up to Beijing then to Tianjin then back to Beijing then fly home from Beijing to UK.
Flights and accommodation not yet booked - does it need to be for application for myself and husband?
Can I bring passports through to Edinburgh and apply for entry permits in one day? If so does my husband need to come through too as he works so not so easy for him to attend during day?
How many photos are needed for each application?
What is cost?
How do we make appointment?
Looking forward to our visit to China so hope you can help with above questions - thank you