You're DSLR setup was just right and you've also pressed the shutter at the right moment. Your photos all look good on screen but the last thing you want to do is to have them printed by a mall chain's photo lab; especially if the photos are for your clients.
Photo printing is a serious business and a good photo lab can print out a digital file exactly as it is seen onscreen (or really, really close). Consumer labs just won't cut it since they cater to just about anyone who has a camera. These kind of labs specialize in printing pictures captured by point and shoot devices so their equipment automatically adjust the colors in a digital file without a human spot-checking on the changes. They also use lower grade inks and papers to keep their prices accessible for the general population.
Professional photo labs, on the other hand, are generally more expensive because they serve professional photographers who demand quality. All color corrections are done manually or they can leave a picture untouched if instructed. Of course, all decent photo lab would only use commercial equipment and professional grade materials.
There are a lot of factors to consider when choosing a photo lab, but it goes on without saying that your preferred photo lab should be consistent in producing professional photo prints. It's not just the equipment, quality photo printing has a lot do with the men behind the equipment. A shop that has the latest inkjet and digital RA-4 printers and uses Kodak Professional Endura paper, won't produce quality prints if their staff are inexperienced.
Here's a tip: Try sending out a test photo to several labs to see which one will produce the best print. You can also strike a conversation with lab employees to gauge their technical know-how and gain more insight into their process.
Prices are another thing to consider but just make sure you're not sacrificing quality for a few dollars in savings. A good customer service is a plus; it's very re-assuring to know that a photo lab cares about your work and satisfaction.
Online photo labs have also sprouted up recently. They usually have software that allows customers to upload their photos and leave detailed printing instructions. They would then process your order and deliver the prints to the address you specified. Turn-around times can vary from 24 hrs to one week depending on your order and the company.
In closing, people still want to have pictures printed out despite the proliferation of digital photo printing and storage. You might be hurting your name as a photographer by giving your customers less than stellar prints. Spend the time to search for a quality photo lab and have them print your photos. It might not be cheap, but the print they produce will reflect upon your work as well.