Pattaya: You will find there's every day bus that leaves Phuket, travels via Bangkok within the wee hours of the morning, and deposits you in Pattaya each morning. And vice-versa. This eradicates the trouble of making bus modifications, even bus station changes, in Bangkok. There are many complications, even so. https://travialist.com/story9250728/the-5-second-trick-for-%E0%B9%80-%E0%B9%80%E0%B8%A1-%E0%B8%A2%E0%B9%80%E0%B8%9E-%E0%B8%AD%E0%B8%99%E0%B9%84%E0%B8%A1-%E0%B9%80%E0%B8%8B-%E0%B8%99%E0%B9%80%E0%B8%8B%E0%B8%AD%E0%B8%A3