If you have a professional housekeeping service clean your home, you may want to find out about its vacuuming habits. Many companies use their own equipment, bringing it from house to house. The problem? Cross contamination between houses -- things like pet dander, mold and mildew can transfer from another house to yours. The simple solution is to insist the cleaning company use your own vacuum inside your home. While you're at it, you can insist it uses eco-friendly cleaners that you provide, too. Some franchises prohibit the use of unapproved cleaning products, so you may be better suited working with a local service company.