As others have mentioned, make sure that you really love their work. This is one of the most important factors in choosing your photographer. If you love the style and the quality of their work, then you can move ahead in finding out more about them, etc. The next thing to consider is professionalism. Do they respond promptly to your emails and/or phone calls? If not, you probably don't want to hire them to photograph your wedding. And, finally, there is the issue of price. I think that this quote by John Ruskin says a lot about making purchases in today's world:
“It is unwise to pay too much but it’s unwise to pay too little.
When you pay too much you lose a little money that is all.
When you pay too little, you sometimes lose everything, because the thing you bought was not capable of doing the thing you bought it to do.
The common law of business prohibits paying a little and getting a lot.
It can’t be done.
If you deal with the lowest bidder it is well to add something for the risk you run.
And if you do that you will have enough to pay for something better!”
It is much better to cut in one or two other areas of your budget so that you can have really high quality images of your day, than it is to pay too little for your photographer, and then be disappointed in the end. Remember, these images will be passed on to your children and grandchildren.
Best wishes,
Tod