Buy two 6" x 6" paintings and only pay shipping and handling for one.
The majority of paintings done in the last two months has been 16" x 16" or larger. There has been some 8" x 8", but I haven't been able to get anything squeezed in on a smaller panel than that. I have a pile of 6" x 6" panels and I wondered if I would ever get anything done on them. I did give it a go today, and for some reason it worked.