I spoke to a local coffee shop about selling some photos on consignment. I have (2) 8x10 photos that are matted and framed to size 11x14. I have about $30 invested in each photo. What is a fair price to ask? Also, should I have some kind of written agreement with the coffee shop, stating the asking price, how long they will keep the prints, their % of the sale etc? This is my first time selling prints like this, just looking for any advice.