Hire a professional that specializes in their craft.
We are wedding film makers. It is our speciality. It is what we have spent the last eleven years perfecting. It is our craft. It is what we live and breathe.
But consider this...... what if I can make an amazing birthday cake for my 6 year old? Should I start offering wedding cakes as part of our video packages? More than likely, it would turn out to be a disaster and here's why. What about when I am trying to put the final touches on the icing, and you are putting on your dress? Do I not get coverage of you getting ready? That wouldn't be very fair to you that I missed the amazing moment when you realized that you really were an official bride!
My example might be a little extreme, but I would like to get the point across that you should pick vendors that specialize in what you are hiring them for. Just because I can bake a pretty decent cake doesn't mean that I would be able to have the knowledge of transporting it to the venue without dropping it, icing it so that it doesn't melt, or have the business license to even bake it (if that is a requirement for their industry - I really have no clue).
People who offer items outside their expertise can be compared to a shopping experience at Walmart. Hang with me here... Say you need a new pair of reading glasses. You can buy them at Walmart for a really great price but you are not going to have anyone with enough savvy to be able to help you pick out the frame that looks best on you. The best place to go is somewhere that has both the experience and knowledge to fit you with the perfect pair of glasses. Yes, it might cost you a little bit more, but you are gaining the customer service that only the speciality store can give you. In the end you overpaid for the glasses at Walmart (even if they were cheaper) because you're not going to enjoy them, you're not going to wear them and all you'll have left is a headache.
When considering a service from a particular vendor, ask yourself if that vendor considers the service just a product that they sell, or is it a craft? As you search out the perfect partners in the seamingly endless sea of options, you will find plenty of one-stop-shopping approaches to doing business. There will be some vendors that offer everything you'll need for your big day minus the groom, and the prices will be lower. When you find that, ask yourself why that is. As consumers we put up with the lack of service in exchange for lower prices at America's big box retailers. Follow that philosophy on your wedding day and you'll end up in a beautiful dress looking for someone to point you to housewares.