2 x trips

Hi there, I will be travelling from London (on a UK passport) directly to Shanghai, stopping for 48 hours before flying to Tokyo. We are flying back from Tokyo to Beijing, stopping for 72 hours. Is it possible to apply for the 144 hour visa in both of these cities with the 10 day gap in Japan? It seems from the article we don't need any documentation other than a card we'll get when we land and our onwards flights, is that correct? Will any payment be required? Thank you!