Here I am in 2019 beside my trusty Winsor and Newton watercolor tray and just a small number of the 60 sable brushes I have been using for 30 years, give or take a few.
This type of tray will last me about 6 watercolors 16 x 20 painted on imported ARCHES 140 lb watercolor paper. ARCHES is one of the oldest mills in the world and the only paper mill in the world to gelatin size it's watercolor paper "to the core".This simply means that it preserves the lustre and transparency of the colors while preventing paints from penetrating the paper. Very important in order to produce an exceptional quality watercolor that last.
The brushes I use are mixed, but mostly Winsor & Newton Kolinsky sable and Da Vinci brushes. They will last a lifetime with excellent results.They will probably out live me.