Thanks for the ideas! I'm checking them out now, and SaveYa looks interesting on paper (screen). They buy in standard quantities (under $300/mo) or bulk (over $500/mo), but not in between.
I'm wondering if the bulk pays better, and approx. by how much?

Also, did you send them your physical gas cards or the scans? Their process description is not very clear, so any further details would be appreciated.