What is the best way to get cost data, such as inptaient, medication costs, etc? Is the a standard set that is acceptable by various sources?

Does the Home Assessment include surveying the exposure to outdoor air (i.e. status of windows/doors).  Does the Home Assessment survey the outdoor exposures in close proximity (300 yards) to the home?  For example, what if crops are fertilized or crop dusted and are in close proximity to the home?  Folks are always talking about only 15% of time is spent outdoors.  However, patients carry in exposures into the home; whether pollen, VOC's, etc.

Have you been involved or used HVAC and duct cleaning on any of your test homes to reduce the amount of air born particulate to help reduce the irratants that can trigger asthma? If so do you have any current findings?