So we have your images the way you want them and it's time to make prints...are all printers created equal? The short answer is a big fat "NO". A lot of printers produce very poor prints. Some aren't even really photos--they are from an inkjet printer. You might as well print them at home.
Others are well worth the cost. Most premium printers do a very fine job and can be trusted to help get the look you really want but the real surprise is that there are a lot of discount printing houses who do just as good a job. They have the same equipment as the premium printer and if your prints need no adjustment, they are probably your best bet.
To go ahead and name names, among those I use and recommend are: Walmart, Adoramapix, Snapfish, and York. They all do great work and have a fast turn around. If you have problems with a print not looking right, these companies won't be able to help you, however. The technician's just run the file through without adjusting anything and may not even know how to adjust your prints.
Professional printers don't work with the general public (normally), so go back to your photographer with a request that he or she run your file through their pro lab. The pro lab will correct color problems and the photographer can usually handle any other adjustments needed. It's well worth the expense to have prints that look fabulous.