I enquired with an estate agent to view a house that has just come on the market. They are having an open day on Saturday but said it booked up within half an hour of posting on Rightmove and they are not allowing any other viewings unless they don't get a suitable offer from the open day. This seems a bit weird to me, as I (and others) might be willing to make a higher offer than those who are booked in. Is it common practice to limit the number of people that can view a house?