Unlike you, I have taught middle school for a Chinese agent who supplied me with a teaching assistant, for 5,000 RMB/ month plus most of the perks you mention, and I was never skint at the end of a month. I was posted in the sticks, the cost of living was low, the locals were friendly, and life was at a slow pace.

Well, like you, but not feeling a need to boast of it, I got 5,500 for a similar gig. But no TA in my class, and I preferred it that way, then I could as I please, no stupid textbook, no stupid games, I was free to do as I please. A lot of times they had exams, went home, so some months I only taught two weeks, hardly work at all.

The OP prefers training centres, not much we can do about that. Personally they are not my cup of pu er tea.