More Art Tour Opportunities

Having received the former suspicious request for a commission I am now somewhat more sceptical of another opportunity that has come my way (or not) today. I received an email from an online art gallery offering me the opportunity to be one of 12 artists to have my work blown up and put on a billboard outside Tate Modern in London. It will of course cost me money. £114 to be exact. £25 to register with them and £89 for the privilege of my work being on the bill board. Do I say yes or do I say no. Could be a genuine opportunity ...or it could be someone trying to fleece me!