Actually, Costco does a good job. You just gotta know how to use the fact that they profile and make their ICC profiles available. Go to DryCreekPhoto and learn the steps necessary.
I created an action in Photoshop that converts all my photos that will be printed at Costco.
I had some 8x10 printed at Professional labs such as WHCC and ProDPI. Then had the same images printed at Costco.
The Costco one held up it's own. Very nice prints and very much like what I see. ProDPI uses Fuji Crystal Pro paper, and they had slightly more shadow details. But gosh, you were really A:B comparing and nitpicking.
Otherwise, color tint, there were none.
Whether you're printing at home or at a pro lab or at Costco. You really need to understand and utilize a color managed workflow. That's the key.