Before serving a particular dish to your guests, ask your catering service to allow you to taste the food tit. They may charge a small fee, but it'll be worth it. This way, there will be no culinary surprises on your big day, when it's too late to do anything about it.
Effective catering requires a lot of equipment, but fortunately a good bit of it can be rented. While you'll need your own vehicle and basics like food warming equipment, items like chocolate and beverage fountains, margarita machines, and the like can usually be found at a local rental company.