if it's a single line portal, you don't need to specify either 1 for repetition number or 1 for portal row number. It will just get the first row value by default.
you're trying to get the content attribute for your portal, not the field inside of the portal. Namespace your field and then reference that instead of "labor".
content - returns the content of the specified object as follows. For:
graphics - returns image data such as the name of a file in a if the image is stored (in the field or externally), or the reference to the file if the image is unstored.