There are a number of variations to a residential building survey which offers the home purchaser a choice of products. The two main variants are the RICS Guidance note version stemming from the earlier RICS guidance note 2004 (more recently updated by the "Surveys of residential property RICS guidance note 3rd edition" which was introduced in December 2013). The primary difference between guidance note and the practice note for the consumer is the format of the reports. A bespoke style or a framework (traffic light signal) style. For surveyors guidance is "best practice" and practice note is "mandatory".