For this particular series, I have decided to do all the paintings the same size 400x535mm.
I am working on 3mm supawood boards. There are a number of reasons for this, firstly the board size suits my painting style, secondly boards are strong and smooth, which allows for detail which I find important. Lastly, I have ready made cartons for this size, which makes packaging easy.
I use Acrylic paint, its great for what I do and very durable.