Yes. A quote can be "edited" before the order is submitted rather easily!
Log into My Account
Click on the icon labeled "Continue Project"
to the left of the art/content sections, there will be a link labeled "Edit Quote".
You can change up your quote the same way that you created it but by selecting new options at each subway stop.
Some new selections may affect any art / content uploads that you have made already and may need to be uploaded a second time.
If you have already walked through check out and submitted your order, you will no longer be able to edit the quote yourself and should Contact Us to see if changes can be made at this time.