It is normal practice for the consultant to meet you at the door to register your name and contact details. You will then be free to inspect the property at your leisure. The sales consultant will always be available to answer any questions and provide information on the property or area.
If you have a consultant working with you, ring them when you see an Open Home advertised and they can arrange an introduction or escort you through. After the Open Home the sales consultant will ask for your feedback on the property.