Costco prints way too dark

I sent some photos to Costco for some quick prints. The prints came out are way too dark and unusable. The photos I uploaded contain some photos I edited in Lightroom on a MacBook Pro Retina. The screen was calibrated with Spyder4Pro. There were also some prints of my family made by a professional photographer. Those came out too dark as well.

Is there anything I can do to avoid the 'too dark print' problem besides not using Costco? I typically use MPix for critical work and Shutterfly for non-critical work. This time, I tried Costco because I needed the prints within a couple of hours and there is a Costco nearby.

I just want to find out if it is something I need to do while processing in Lightroom or calibrating my computer to avoid the inconsistent print problem with volume print labs.

P.S. My MacBook Pro was calibrated with brightness set to middle. Is that a problem?

Thanks in advance for any help.

Joe