If you have mold problems despite your best efforts, you have your work cut out for you. In climates that are wet for extended periods like the Pacific Northwest with its long wet winters or the Gulf states with their high humidity, many surfaces don't completely dry out. Condensation along windows and sills or areas where air circulation is minimal are all at risk for developing mildew or molds.
Keeping your home dry is the first defense against molds and the myriad respiratory problems they can cause. The solution to mold problems usually requires a two-pronged solution: clean and remove the mold on any surface it has affected and solve the root problem that is causing the moisture in the first place.
Mold will grow on, into, and through any consistently moist surface. Materials that can be washed, disinfected and rinsed, then dried can be salvaged. Some materials such as plasterboard that has become moldy often needs to be replaced.
At the same time, find the source of the moisture that can be caused by roof, wall, floor, or plumbing leaks, or poorly ventilated bathrooms. Another source of high humidity is a combination of keeping your heat relatively low, blocking heating ducts, or reducing airflow by simply having too much clutter. Once the source has been identified take steps to correct the problem at its source.
Because mold is a health hazard, hiring a competent qualified specialist is important to get the job done right the first time, especially since you may be paying for such problems out of pocket.
Check your contractor's licensing and certifications as required by your state, insurance coverages, and references. Read the contract carefully and make sure that you are getting what you pay for. Find out exactly what the contractor offers in the way of warranties and guarantees to ensure that you solve the mold problems in your home once and for all.