The main points with choosing a wedding videographer include:
This is the main factor in choosing a videographer. Make sure that the price on the contract is the final price. This should include a set number of copies of the final video, along with coverage of any other hidden prices. Make sure you know how long the wedding videographer will be there so that you don't pay a huge amount for any overtime. These should all be included in your wedding video package.
For the sample wedding video, make sure you get to see an actual product that we delivered to a previous bride. This lets you know exactly what you are going to get (as opposed to a fancy, catered highlights reel of different weddings).
(This doubles for your photographer) Make sure you feel comfortable with your videographer. This means meeting the wedding videographer and not a representative for the company. Remember that the videographer will be there working while you have the most important event of your life. Feeling uncomfortable with him will show in the photos and the video. The videographer should add to your day, not take away from it.
Make sure that the videographer has all the information that is necessary. This includes contact information for other key persons, such as the wedding planner, photographer, and venue coordinator. All location information and directions should be provided also. If possible, a timeline of the special day should also be provided.
The videographer should be aware of the structure of your wedding and ready to respond. There might be other features to your wedding that the videographer will have to adapt to. For example, some churches do not allow camcorders or restrict the usage. Your videographer should be very aware of these potentital situtations. Another is that the reception may have exceptionally low lighting conditions (wedding lighting considerations), which would require extra equipment for the videographer.
The videographer should be able to jump from one location to another in a resonable time. This means that you may have to guarantee parking to make sure that the videographer can setup equipment in time.
One thing that I have found really helpful is when either the wedding coordinator or the DJ gives me a heads up for each event. So try and set it up so that while your videographer is busy getting extra footage someone taps on his shoulder 5 minutes before the cake cutting.
After the day of shooting, the wedding video goes into production. This may or may not involve your input, such as for music selection, special requests, and rough drafts. I always leave the option of removing any parts of the wedding video (such as certain guests).
Make sure that the final product is exactly what you expected when you signed the wedding videography contract.