[whiplash]

With a budget of 5-8k you have the means. You might be taken advantage of in Korea but very unlikely to be robbed outright. There are a couple of experienced resident Korean bros in this forum and hopefully if they see your request they may perhaps point you in the right directions. The Tenpros is what you want to look for.
In China you should be careful of scams and never follow anyone you do not personally know. Take care to note this.