Every time I read a post on a wedding forum, I cringe at the ways many brides select the entertainment for one of the most important days of their life. Many are only concerned with price. That should actually be your last question to a perspective vendor.
First, I'll get over the misconceptions with the adage "you get what you pay for" and "wedding DJ's are all pretty much the same". The first quote is very true, and the second quote couldn't be farther from the truth.
There is no regulation for entertainers, so anyone can buy a few speakers and CD player, and print business cards. You'll find many of these folks listed on the budget newspapers, with slick ads claiming to be the "Best Wedding DJ" money can buy. Most probably, the best money can be spent with a little homework on your part.
Wedding DJ's come in all forms (just like with anything else) and the industry is filled with rank amateurs... all the way up to very high class pros, who demand a pretty penny for their services.
When brides post about getting a "great deal" on their DJ, I have to ask: "What did you get for your 'great deal'"? A $500 DJ can be a great deal if he/she brings lots of lights, an amazing sound system, and a huge library... but I have to tell you, you're not going to get all that for $500. The best way to determine what you're going to get, is really based on your budget.
If you have $500 to spend, then be reasonable with your expectations. Far too many brides think they are going to get their "fairytale" experience on that $500 DJ budget. Not so! $500 (or so) will buy you a good quality DJ with a basic sound system and a few party style lights (assuming he/she is a pro with skills). You can spend several thousand on a high quality DJ with lots of amenities... so how do you pick the best one for your budget. Good question...
First, does you DJ have a web site? Many brand new DJ's don't have a web site when they start out. That isn't a sure fire way to determine if your DJ is quality... just that they are new or inexperienced. I've heard of DJ's performing their first show, who came out of the box with a "smokin show"... but they did their homework first, and so should you. Here's what you should ask:
How long have you been in business?
How many shows have you done & what type of show?
Do you have liability insurance on your company when you perform?
Do you have a web site?
Do you use professional equipment?
Do you have any videos/photos to watch or look at?
Do you use a legal contract?
Do you attend any industry training seminars?
How much time do you need to set up and tear down?
Do we need to meet with you to plan and organize our event?
What kind of music do you play and do you take requests?
How many songs in your library?
Do you have different shows based on budget? What are those?
Now, I'll address some of those questions with what you should be looking for:
Many "newbie" DJ's offer great prices because they want to grow their business. You may get a diamond in the rough shopping this way, but keep in mind that you may have inferior equipment, skills and music choices with a new DJ. Growing a successful business takes time and effort, and lots of dedication. A DJ that has only a few events under their belt, will undoubtedly make mistakes and have a few glitches, so keep that in mind. Most new DJ's can't afford insurance, so any legal issues will not get resolved if you have any.
Professional DJ's have "road ready" gear, that is high quality, and back up equipment should there be a failure. Professional gear is not what you'd see at Best Buy or Target. Professional DJ gear is expensive. A good quality sound system alone, can cost $10,000 or more.
Make sure your DJ has a contract that protects everyone involved, and is written in clear understandable English. Your contract should outline every important aspect of the event. If your DJ is regularly attending training, you can assume they are dedicated to the profession, and WANT to give you a high quality performance for your hard earned money.
If your DJ has videos or pictures, you need to look at every one of them. This will give you an idea of their skill, and attention to detail, not to mention they type of performance style they have and how they react with the crowd. Also make sure your DJ has a lot of the "style" of music you like, but keep in mind that you are having a "party" so don't play every song you personally like; your guests want to have a good time... not listen to your jogging music.
Many DJ's can custom tailor a show to fit your budget, so be sure to ask what's contained in the show you are asking about. For example, I have a "low budget" show for under $600, that has only three small speakers, and a few nice computer controlled lights. I also have a high tech show for $3995 that rivals a Las Vegas production, and a sound system that will fill a gymnasium... so be sure to ask what you get for your agreed upon price.
Ask your DJ if they have "uplighting". This is new to the industry, and is currently being offered by the high end performers, with a lot more computer skills. These lights wash your walls with color, and can totally set the "mood" of any room where they are installed.
Most importantly, read everything you can find about your performer. Check blogs, YouTube, Facebook, and "Google" their business name. If they don't show up, you are taking a risk.