In-home visits are useful for either verifying the accuracy of information gathered by telephone, or collecting observable information that respondents may not conscious of. For example, ODC's energy group conducts in-home visits to verify quantities and types of lighting in a home, and the energy efficiency of different types of appliances.

ODC's customized eeSiteAuditor™ software allows ODC auditors to work on PDAs to electronically enter data; this eliminates data transfer issues, and reduces the need for additional data entry.