An answer for you.

A reader asked me where I got the pans for my greenhouse.  The answer is I got them at Lowes.  They are cement mixing pans and are about 2x3 feet.  I found some smaller ones but these are the ones I wanted.  I think they are at least ten inches deep. 
Thank you for the question.

If I remember right they cost around $13.00 each.  I am thinking I want to buy 6 more to put on the floor for another level of growing places.  I can put things down there that aren't harvested as often and just need a place to grow such as beets.