Here are some common ones and some solutions:

•   The pet door is going to leak and you'll freeze in the winter or lose all your cool air in the summer.  The solution:  Get a pet door that seals very well. The "Endura" flap pet doors have been tested from below zero to 130F without losing their seal.
   
•   The pet door won't insulate. Same problem but not as serious as not sealing well. "Endura" flap pet doors won the coveted Fancy Publications Editors Choice Award for 2007.
   
•  Your dog is going to track mud all over the house. Some people have a "mud room" that the pet door opens into so the mess can be contained in one area. This is often a laundry room. But what if you don't have a mud room? The solution: The Hugo Pet Products Foldable Pet Shelter. This nifty device mounts on a door, drywall, cement or stucco and "contains" your pet until you can get there to clean him up! Folds quickly and neatly out of the way.
   
•  You want to let your pet outside for some fresh air but have no way to control him. Same solution as above:  The Hugo Pet Products Foldable Shelter contains your dog or cat on the inside or on the outside. Can be mounted on a door or wall.
   
•   The aesthetics aren't good. It's true that most pet doors have a utilitarian look about them. Check out the "Classy Custom" Pet Portal line for an exception to his problem.
   

The award-winning "Endura" flap both seals and insulates

Hugo Pet Products
Solves the Mud Tracking Problem!

Classy Custom Pet Portal