Art tools for the trip

#Porto Urbansketchers Symposium is coming very soon and it is time to decide what to bring and pack for the trip. It is always a struggle to decide especially the art tools. I need something I can be mobile with so oil painting is out certainly. To paint in comfort I still need the stool, the easel and the palette tray. These are definitely in. The problem is, should I even paint with watercolour?

Done