I have done a couple of those over the years, and I will tell you that you will lose money, there totally useless and there are many other ways to use the space more effectively.
With that said, if they insist on it, make sure they pay dearly and you dont end up losing any chance of a profit just so they can show it to their friends, then you end up getting more of them and losing some more money!@!
![Mad :x](./images/smilies/icon_mad.gif)
![Frustrated :wall:](./images/smilies/pictowallsmall.gif)