If a customer has print ready artwork my pricing would be:
3M 40C w/ 3M 8508 Overlaminate - $5.50 / Sq.Ft.
3M 40C w/ 3M 8518 Overlaminate - $6.75 / Sq.Ft.
3M IJ180CV3 w/ 3M 8518 Overlaminate $8.00 / Sq.Ft.
Mounting to a substrate that is ready for application (just a rub down with alchohol) is $.50 / Sq.Ft.
For my area I think I've got pretty good pricing but I still get underbid by another local
sign company that works from home and likes to work for just about nothing. I would charge extra for setup / design time if the artwork is not "print ready" and I wouldn't offer a discount until they hit about 300 sq.ft.